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Garmin Forerunner 645 Music GPS Running Watch In-Depth Review


It’s been almost two months since Garmin announced the FR645 and FR645 Music (aka FR645M), its first wearable with music onboard.  Past Garmin watches could control music on your phone, but none could have music loaded on it and play directly to headphones. Of course, such a feature is (or was) hardly unique to Garmin. Countless running watches have had it for a while. From TomTom to Timex, Apple To Fitbit, and many more.

In any event, now music is here.  But it’s more than just music – after all, the FR645 comes in two variants, music and non-music.  At its core it’s a running watch, with a swath of new features compared to Garmin’s past running-specific watches.  Not to mention more unique functionality like contactless payments that Garmin only recently introduced last fall.

With Garmin now actively shipping the Forerunner 645 Music to customers, it’s definitely in-depth review time. I’ve been using the watch since this past December, and it’s been on my wrist virtually 24×7 (except the roughly once a week I’d charge it up). Runs, rides, swims, and all sorts of randomness in between. First in beta, and now with final software.

As always, I’ll hand back this loaner/test unit to them and go out and get my own from regular retail channels. Feel free to hit up the links at the end of the review to help support the site if you found this interesting. With that, let’s dive into it!

Weights & Sizes:

First, let’s take a look at how it compares in size to the FR630 and FR935, both of which are pictured on either side of it below (Left to right: FR630, FR645, FR935). As you can see, it’s the smallest:



As you can see, the FR645 is smaller in width than the others, though about the same thickness.  I personally like a lightweight watch (compared to say, the heavier Fenix series), so my go-to watch is normally a FR935.  This feels on my wrist basically the same to that in terms of weight. So I’m happy there.


Also, as noted the bands are the same as the Vivoactive, which means they’re standard quick release style 20mm watch bands.

In my case, Garmin thought it’d be funny to send me a watch with a pink band on it – called ‘Cerise’ by Garmin, which ironically enough, is simply French for ‘Cherry’.  And I actually wore it around for about 10 days that way before I swapped it for the black band from my Vivoactive 3.


As for weight, the unit comes in at 42g:


That stacks up as follows:

Garmin Vivoactive 3: 43g
Apple Watch 3 LTE 42mm Size: 63g
Fitbit Iconic: 43g

In case you’re wondering why there’s no unboxing section here, the reason is simple: I had the unit shipped to me sans-box. Just the charging cable and watch. I’ll add an unboxing section in here once I get the box, probably in a week or two.  But I didn’t want to hold up all the technical juiciness over some pretty cardboard, and of course safety manuals you’ll never read.

The Basics:


In most ways, if you’re familiar with any Garmin watches made in the last 1-2 years, you won’t find a lot of difference with the FR645.  Especially if you’re familiar with the Fenix 5 or Forerunner 935, as the FR645 almost entirely mirrors those watches.  In fact, it’s probably worth briefly pointing out the core new features found on the FR645 compared to both its predecessor (FR630) and its siblings (Fenix 5 series/FR935). Here’s what’s new:

– Added Music storage and playback via Bluetooth (first Garmin watch to do so)
– Added Garmin Pay (NFC contactless payments)
– Added Garmin’s latest Elevate Optical HR sensor (same as FR935), for 1-second 24×7 HR recording
– Added Bluetooth Smart sensor support (like FR935, FR630 didn’t)
– Added FirstBeat Training Status metrics – fitness load/recovery (FR935 has it, FR630 doesn’t)
– Added Lactate Threshold tracking (FR935 has it, FR630 didn’t)
– Added latest Garmin Connect IQ for apps (FR935 has it, FR630 stops at older version)
– Added indoor pool swimming (FR935 has it, FR630 didn’t)
– Added Ski/Snowboard sports (FR935 has it, FR630 didn’t)
– Added SUP/Row/Yoga/Elliptical/Stair Stepper/etc sports (FR935 has it, FR630 didn’t)
– Added HRV Stress app (FR935 has it, FR630 didn’t)
– Added Strava Live Segments (FR935 has it, FR630 didn’t)
– Can respond to text messages from watch (only for Android users for now)
– Can follow courses (FR935 has it, FR630 didn’t)
– Uses similar charging cable to FR630. Identical from exterior, but internally is different.
– Uses same new quick release bands as Vivoactive 3

Phew – got all that? If you’re familiar with the FR935/Fenix5, then basically it can just be summed up as “Added music and Garmin Pay, took away multisport/openwater modes, and advanced navigation”, roughly.

Still, starting at an even more basic level than all those features we’ve got the widgets/apps and watch faces. You can download more of these from Garmin’s App Store, which has thousands of them. Here’s a quick gallery I shot of some of the default widgets, which include things like your daily step totals, your current heart rate, and the weather. Most of these you can tap to get more information:

The watch face itself is customizable too – allowing you to change what information is on it, even if you don’t want to go as far as downloading a 3rd party watch face (which still only takes a few seconds).

From an activity tracking standpoint the FR645 tracks steps, stairs, and sleep (as well as heart rate 24×7). You can see these steps in the gallery above, as well as the heart rate pieces. All of this data is then sent to Garmin Connect Mobile (the phone app), and onwards to Garmin Connect (the website). Here’s a few random screenshots over the past few days:

2018-03-06 13.10.46 2018-03-06 13.11.05 2018-03-06 13.12.10

When looking at accuracy of step data I find it basically in-line with other tracks that I’ve worn on those given days, plus or minus a few hundred steps.  If I look across the industry at activity/step tracking, no device is perfect. Every device has their quirk on a given activity or thing that it does funky (for example, one device may correctly not count steps while washing the dishes, while another doesn’t do as well pushing a shopping cart).  My general attitude here is that as long as a given device isn’t overshooting by thousands of steps, you should use these metrics as a general guideline for the day.

In other words – if your watch says you only walked 683 steps that day, you were likely a bit…lazy.  Whereas if it says you walked 15,382 steps that day…then kudos. I don’t tend to fret too much if it was actually 15,029 or 15,683 – either way, lots of steps.  Trending is what you’re going for with step counts.

As for sleep – things are generally pretty good here. The unit seems to nail my falling asleep and waking up points just about perfectly each night.

2018-03-06 13.12.46 2018-03-06 13.12.39 2018-03-06 13.13.53

The only catch is it doesn’t track naps at all – those just disappear into the ether. Not a huge deal for me personally since naps are fairly rare, but since I took one two days ago it happened to remind me to mention it.

Next, there’s continual heart rate. The unit has Garmin’s most recent ELEVATE optical HR sensor, which is now enabled for tracking at 1-second intervals, 24×7.  In my experience these 24×7 measurements are pretty accurate. Sometimes I’ll wear a chest strap to compare the 24×7 measurements and the two are usually within a few beats of each other.  Note that I dive into the sport-specific optical HR measurement down below in far greater detail.

You can track your resting heart rate either on the watch or in the app.

2018-03-06 13.19.32 2018-03-06 13.15.43

As with the past though, I don’t put a lot of stock in this number.  There’s plenty of disagreement on what exactly resting HR is (in terms of how it’s defined), but consistently Garmin overshoots my resting HR values.  I can sit down at my desk and get my HR down to 41bpm…but Garmin says my RHR value for the day is only 46 or 51 or something in that range.

Next, I should mention somewhere that the screen is not a touchscreen (thank you!). Instead, you’ll use the 5 buttons on it to navigate your way around the interface.  If you want a touchscreen, the Vivoactive 3 has that (though, sans-music and other feature), but personally I just find a non-touch screen works better in most running situations, especially involving intervals or such.

Garmin-FR645-WatchFace Garmin-FR645-Buttons-No-Touchscreen

From a backlight and visibility standpoint, I find the screen a bit more clear than the FR935 for some reason. It just feels sharper, which you can kinda see in the comparison section photos up above.  Similarly, I used the older FR630 on my run a few nights ago and forgot how poor that screen is compared to the FR645. Wow, totally different world.

Oh, and lastly, from a battery standpoint, Garmin states that the FR645 can last 14 hours in GPS mode, 5 hours with GPS+Music, and then up to 7 days days in standby mode.  Keep in mind that standby number is based on not using it in GPS mode.  In my real-life usage, I’m finding that I need to charge it roughly every 5-7 days, if I’m using it roughly once per day for an hour in GPS mode (some days less, some days more, but rough ballpark).

Sport Modes:


So ya wanna head out for a run do you? No problem, obviously this watch does that – it’s officially a running watch after all.  But unlike past Garmin running-specific Forerunner watches, this also tracks indoor pool swimming, and heck even sports like skiing, snowboarding, stand-up paddle boarding, and rowing…among many others.  None of these are new though to folks coming from the multisport or Fenix lineups, or even some of the Vivoactive watches.  But all are new to Garmin’s running-specific forerunner lineup.

Still, we’ll start with running and go from there into a few of the other sports.  To enter the sport mode listing simply tap the upper right button, which opens the sport menu:


You’ll see your favorites listed (which you can customize), as well as select lesser used sports.  Once a sport mode is selected it’ll go off and find GPS (if applicable), as well as your heart rate.  It gives you small icons at the top for the status of that, plus any sensors connected.  Also, the GPS signal status is shown around the edge:


Once you press start you’ll be in the recording mode, which means it’s now tracking what you do. Within the FR645 you can have a boatload of custom data pages, as well as standardized data pages.  I say a boatload because I’ve added 6 custom pages now and I got bored of adding more pages. There doesn’t appear to be a practical limit.  This is in addition to special pages like the map view, graph pages, running dynamics, music control, and heart rate zone page.  Within a given page you can customize up to four pieces of information.

Here’s a small pile of what these look like to get some pretty data shown while running:

Note that pages like the Running Dynamics one do require you use a Running Dynamics capable sensor – such as the HRM-TRI or HRM-RUN, or the Garmin RD-POD.  These also work with 3rd party sensors that support the ANT+ RD Profile, but at present nobody has done so.

In addition to standard pages, you’ve also got functions that include auto lap (based on a pre-defined distance of your choosing), lap banner customization (to specify what info is shown when a lap is triggered), auto scroll (constantly changes your data pages while your run), auto pause (pauses the timer at a stop-light), and metronome (self-explanatory).


Then we get into the more training-specific features.  And it’s some of the nuances here that differentiates between something like the Vivoactive 3 and the FR645.  For example, the FR645 includes the ability to download custom workouts you create from Garmin Connect.  Similarly, the FR645 allows you to do interval workouts on the watch itself (without downloads), as does the Vivoactive 3.  But in the case of the Vivoactive 3 you’re restricted to a predefined set, versus on the FR645 the world is your oyster.


I did this for this mornings run, which automatically iterated me through each of the steps in the workout, giving me a countdown gauge as well.


In addition, features like Lactate Threshold testing and paces are available on the FR645 but not the Vivoactive 3.  As with all the Running Dynamics pieces, only the higher end running watches have those.  Further, functions like racing a past activity or doing course following are both not available on the Vivoactive 3.  Note that the lactate threshold function (either the manual guided test or the automatic recognition) requires a chest strap, as that’s currently the only way to get HRV/RR data while in a workout.


Speaking of navigation, the FR645 includes a dumbed down variant of what you see in the FR935 and Fenix 5.  But specifically it doesn’t include all of the software functions such as POI’s, bearings, headings, and so on.  Instead, you’ve got three basic pieces: Courses (following), Activities (re-trace a past one), or Saved Locations (Navigate to a location you’ve saved on the watch, from the watch):


Also, note that the FR645 does not include any maps (nor any way to load them).  You can load apps though like DWMap, which can somewhat fill in that gap for you.  But it won’t make your watch a Fenix 5X (which does have maps).  On a FR645 you simply get a breadcrumb trail style map, such as below:


Circling back to that run we started a while back, once you’ve completed your run you’ll go ahead and get summary information.  You can access all this info as well within the history page afterwards.

Garmin-FR645-History-Page3 Garmin-FR645-History-Page1 Garmin-FR645-History-Page2

In addition, you’ll get all of the new FirstBeat driven training load and recovery metrics.  These metrics were introduced on the Fenix 5 a year ago, and carried through to the FR935 and in lesser bits to other watches too.  All of that is identical here.

Garmin-FR645-FirstBeat-Training-Metrics Garmin-FR645-Firstbeat-Training-Effect

So for example, you can always check your Training Status from the dashboard widgets, which shows you where fitness and load is:


Note that I’m not going to re-write my deep-dive into those features in this review (since it’d be a duplicate), but check out this linked section of my Training Load section of my Fenix 5 review, where I go into detail on how it works, along with a bunch of behind the scenes insight from the FirstBeat folks.

It’s here that you can get the detailed recovery hour metrics:


Same goes for current VO2Max and race prediction times.  Note that both of these are heavily biased towards having some solid interval workouts under your belt with the watch before they get accurate.  Also, FirstBeat and Garmin both recommend wearing the watch for at least a few weeks of running to get full data.  All-in FirstBeat will reach it’s best predictions around training load at about four weeks in.


Do note one caveat here though: It won’t account for cycling workouts in load.  That’s because the algorithms there require a power meter, and the FR645 doesn’t support power meters.  Adding injury to insult here, Garmin still doesn’t yet cross-compute the FirstBeat data from multiple devices.  So even if you bought a brand new Edge 1030 for cycling, that training load/VO2Max data from that unit won’t transfer behind the scenes to your FR645 to form one cohesive picture.

Garmin says they’re working on it, and in fact just yesterday committed that this feature will roll out starting in April to devices that support these new metrics.  It’s already being used/tested internally at Garmin. Specifically, the following units will cross-transfer the advanced data:

Edge 1030
Fenix 5/5S/5X
Forerunner 645/645 Music
Forerunner 935
Vívoactive 3

I’ve yet to see it in action, but from talking with them they’re saying that the various FirstBeat driven metrics will then sync across the board between the supported devices listed above.  So if you go for a run with the FR645, it’ll have the training load data from your Edge 1030 from the day prior accounted for.  As for why older devices aren’t supported, it’s simply that none of those older devices have these specific FirstBeat training load/recovery metrics (they do have variants of other metrics though). A simple way to remember which devices are compatible and which aren’t is that it’s basically devices made from 2017 onwards that support the new FirstBeat metrics that are generally only on higher end devices.

Finally, shifting to a few other sports briefly, first we’ve got swimming. Remember the FR645 only supports pool swimming and not openwater swimming.  For openwater swimming, you need a full Garmin multisport watch.  Within the pool mode though you’ll go ahead and select the size of the pool:


And then from there you’re ready to roll.  Note that the unit will NOT download heart rate data from a Garmin HRM-TRI or HRM-SWIM strap though.  That too requires higher end units.  Also, it will not display/record workout HR data while swimming (like Garmin’s other watches) from the optical HR sensor.  Given that other competitors like Suunto and Polar are doing this, it’s probably time for Garmin to reevaluate their position here.


Once you’re done with the workout you’ll be able to upload all that goodness to Garmin Connect and look at your lengths/sets there:


You can also change the tab to look at the specific intervals. Again note though that no heart rate is displayed here.


Switching gears again, if cycling you’ll get basically the same metrics you would on most bike computers.  It can pair to ANT+ or Bluetooth Smart speed and cadence sensors (speed-only, cadence-only, and speed/cadence combo).  It will NOT connect to power meters of any type.  I’ve used it on some rides, and the FR645 works fine for accurately tracking all your core speed/distance/time stats (as seen in the GPS accuracy section down below), plus cadence if you connect that sensor.  But for me, I ride with a power meter, so it’s not really the right device for me for that sport.

Finally, since I briefly touched on it a few paragraphs ago – the FR645 follows in the footsteps of the Fenix 5 and FR935 and basically all of the devices Garmin introduced from 2017 and beyond in that it supports both ANT+ & Bluetooth Smart sensors.  This includes the following sensor types:

– Heart Rate (ANT+ & Bluetooth Smart)
– Speed/Cadence (ANT+ & Bluetooth Smart)
– Running Footpod (ANT+ & Bluetooth Smart
– VIRB Action Camera (Garmin, via ANT+)
– Tempe temperature sensor (Garmin, via ANT+)
– Cycling Lights (Garmin/Cycliq/Bontrager/See.Sense, via ANT+)
– Radar (Garmin, via ANT+)
– RD Pod (Garmin, via ANT+)
– Muscle Oxygen (via ANT+)
– Extended Display (Garmin via Radar), via ANT+)
– Headphones (via Bluetooth)

One little bit of trivia there is for every category above where it says “(Garmin, via ANT+)”, all of those are actually open standard sensor types, it’s just that in most cases nobody else is using the ANT+ standard for that category.  For example, anyone can build a radar and use that and have it work with Garmin devices.  Same goes for the action cam control, which is actually just an open standard there.  We’ve seen some companies take advantage of that within the cycling lights realm, and perhaps soon some for the RD Pod (ANT+ RD Profile).

Of course, we don’t see equivalent standards for many of those device types on Bluetooth Smart, hence why they aren’t supported there.

If you’re wondering what’s missing from the above list compared to a multisport watch, it’s basically just ‘Power Meter’, and in the case of cycling-specific units it’s also ‘Cycling Trainers’.  Thus as you can see, it’s a pretty comprehensive list (including lots of cycling stuff) for what is otherwise ‘just a running watch’. I suspect the goal of including things like lights and radar would be to attract commuter cyclists who might use those devices and not necessarily bother with a full cycling head unit each day.

Overall though, for me, it’s worked well as a running watch, less so for cycling for the lack of the power meter piece.  Of course, be sure to dive into my accuracy sections down below for my full thoughts on that.



Next, let’s dive into the feature that everyone wants to talk about – Music.  This being Garmin’s first music-enabled watch device, there’s lots of interest here.  Do remember that this section only applies to the ‘Music’ variant of the FR645 (aka ‘FR645 Music’, or ‘FR645M’), it doesn’t apply to the non-music variant of the FR645, as that lacks the hardware required to have music.  Which is a good point.  Some will ask whether Garmin will add music to XYZ previous watch.  The simple answer is almost all those watches lack two and a half core things: A) Storage for music, and B) The right Bluetooth hardware to handle music, and, to a lesser extent C) Battery planning to handle music, since it is a battery drain.

Which brings us to the FR645 Music, and it has those things.  It has about 3.5GB of storage for music.  Though technically, that’s actually for music, your workouts, and any apps you have.  But realistically those non-music things only take up a few MB in total (.001 GB).  Technically the unit has 4GB, but half a gig is taken by the system.  Garmin estimates about 500 songs can be stored.  When you plug your FR645 into your computer, you’ll see how much music storage you have left using Garmin Express:


When it comes to transferring music to your device, it’ll transfer via either WiFi or USB cable depending on what you’re transferring.  For simple music you want to transfer that’s not all tangled up in rights protection stuff (meaning, simple MP3’s, Podcasts, etc…), you’ll just use Garmin Express on your desktop (seen above).  You can see the different categories of music listed below. These are essentially just linked to different folders on your computer.  So you’d link the podcasts to the podcasts folder and so on.

This design does mean that for most non-streaming music, you’ll have to update that via your computer.  That’s a bit unfortunate for things like podcasts which could ostensibly be updated via WiFi as with the streaming services.  Garmin is saying though that longer term they’ll look to find ways to make some of these non-streaming options (like podcasts) leverage WiFi directly – but as of today, it’s all locally via cable.

Speaking of streaming services, Garmin is rolling out with iHeartRadio and Deezer.  iHeartRadio is largely focused on the US market, while Deezer is more popular in Europe.  To be even more clear: I’ve had zero success using iHeartRadio outside the US, no matter how much money you pay for a subscription.

What’s actually really interesting is how these services appear within the watch once setup.  See, Garmin’s gone with a ‘Music Provider’ model, meaning that providers like iHeartRadio and Deezer can plugin to the underlying music platform in the watch, as opposed to having totally separate/complex apps (such as most other watches).  For example, within the watch under providers you’ll see I have iHeartRadio and my local music listed, both as sources for music.  Down the road that would also show Deezer, and perhaps further down the road other streaming/music platforms.

Garmin-FR645-Music-Providers Garmin-FR645-MusicProvider-Sync

At present, with iHeartRadio the playlists are updated via WiFi, which is pretty cool.  So as long as you’re near one of the WiFi networks you’ve configured in the watch for general use (I.e. uploading workouts), it’ll upload that way.


Since I haven’t been to the US in the last two months, I haven’t been able to double-check that everything is exactly the same as then, however, essentially with iHeartRadio it’ll pull the updated music playlist via WiFi each time you connect the app or via music sources.  That in turn means it’ll pull the actual songs as well.  While its doing this via WiFi it’ll actually shows you how many songs are downloaded/remaining. It’s kinda nice.  The downside? As of this writing Garmin is still about 1-2 weeks away from having iHeartRadio go-live on the Connect IQ app store.

As for Deezer? It’s not available yet, and the timeframe for that is slated as late April or early May. Eeks.

But let’s talk more generally about how music works.  To get music playing on the watch you’ll first need to pair Bluetooth wireless headphones (or any Bluetooth device – even a car).  There’s no music speaker on the watch itself, so it’s gotta go out via Bluetooth.  To pair headphones, you’ll go to the same place you’d pair sensors and such, and you’ll see it listed there:


You’ll enable pairing mode on your headphones and then a few seconds later the watch will find it:

Garmin-FR645-Headphone-PairingNew Garmin-FR645-HeadphonePairingPart2

You can have multiple headphones paired/saved, which is kinda cool (many watches don’t support that).  For example, I’ve paired the Beat’s PowerBeat’s 2, the Fitbit Flyer headphones, an Amazon Basics speaker and some generic MPOW headphones (only $20!).


Garmin has a list of validated headphones, but that doesn’t mean yours won’t work if it’s not on the list.  It’s just simply ones they’ve validated/tested.  You’ll notice Apple’s AirPods aren’t on there. It sounds like things are a bit rougher with compatibility there, which matches what a few people have seen in the Garmin Forums on that.

With headphones all saved, you’ll wander back to the music widget.  This is accessible anytime by pressing the up/down buttons:


Next, you have ‘Source’, which selects from the music providers, or to simply control music on your phone instead.  Within a given source, you’ll see playlists, artists, albums, songs, genres, podcasts, and audio books (depending on the source of course).


Back on the main controls page, you’ve got a volume icon to increase/decrease volume, as well as play/skip/back/repeat/shuffle buttons:


Once you’ve started playing a given playlist/source/album/whatever, it’ll go to this main screen which shows the current song information – and will even show the album cover when available/transferred, which is kinda cool.


When in a workout, it all works almost identically, except that you can long-hold the lower left button to go directly to the detailed music control page.


So how’s connectivity and how well does it work?  Overall, pretty good.  I’ve been using it with the various headphones noted above, and things work well.  One catch, anytime you talk about headphones and watches (since the beginning of time) is that every headphone out there has one side that’s considered the master/communications side (I.e. left or right).  In general, things work better when the watch is on the same side as that.

For example, on the Beats I’ve been using, that master side appears to be the left side.  For one run I was wearing the watch on my left wrist.  When I was running, I had no dropouts at all.  But, if I stopped running and walked (so my wrist went down to my waist), and then tilted my head to the right a bit – that tiny bit extra put it out of range and I’d get drops (remember, I’m fairly tall).  When I tried the watch on my right wrist instead, I got constant drop-outs.


Again, anyone has used various headphones with watches knows that these sorts of quirks are 100% par for the course.  Some headphones are better than others, and Garmin’s list shows which ones work best and in what configuration.  Other companies like TomTom, Polar, and more all have similar lists, and it’s pretty easy to see the trends in them on which headphones have the best connectivity.  Obviously, that’s also a balance on Garmin’s side too in terms of power management.  This isn’t a car or a plugged in stereo, thus, battery life power management is a balance in any wearable.

Oh, and last but not least, while in a workout, when you press the lap button (or if auto-lap is configured), then you’ll get audio alerts for that lap.  The music will silence itself, and then a voice pipes in with the current lap time/pace/etc depending on how you have it configured.  Basically, just like every other music-running app/device has worked for years.

Finally, for those geeks in the house, when plugged into a computer, the unit shows up as a MTP device (Media Transfer Protocol), which is sorta a cross between a generic USB drive and one focused purely on music.  Though, you can force it to a straight USB drive via settings if you want.  Note that these settings are on the watch.  On a PC it shows up slightly more accessibly than on a Mac, but both ways it will appear just fine.

Technically, there’s two ‘portions’ to how it appears.  The first is the music section/folder/drive/whatever (called Media), and the second is the typical Garmin one (called Primary).  The ‘primary’ one is where you’ll find the workout files and such.  Again, a typical user probably doesn’t care about this, but geeks like me might (ok, geeks definitely want to know this).


Another random geeky note – the cable for the FR645 Music is identical looking to that of the FR630.  Except internally it’s not.  The older cable (for the FR30/35/230/235/630/735XT) they found was causing some issues when transferring music, and thus had to be redesigned for a higher current.  If you plug in the watch with an older cable it’ll charge just fine, but it won’t enumerate on your computer for transfers (of any type).  You’ll get an error message on the watch.


Just a minor heads up for those in a multi-cable family like myself that you might want to mark that one as the golden child (it officially will also has a ‘1A’ marked on it). But I marked it for now with a simple zip-tie to spot easily from far away.

Phew – got all that?!? Good!

Overall – the music works well for me using mostly offline content (meaning, non-streaming services), simply because that’s what I can actually use day to day.  When in the US I was using the iHeartRadio content and that also worked better than I expected it to once on my device.  It’s just that I’m not really an iHeartRadio person (since I don’t live in the US), and with Deezer not available yet, that’s a sticking point.

Personally, I’m a Spotify person (or Amazon Music), neither of which are supported on the device. It doesn’t sound like there’s much near-term promise for Spotify, as they’ve rebuffed almost every company in the industry for wearables support.  Obviously, Garmin and Fitbit and others would likely love to have that solution on their units.  At least the good news is that if other companies come to the streaming table, the underlying music provider model Garmin has adapted makes it easy to roll out new entities. Now we’ve just gotta hope that happens.

Garmin Pay:


As of this writing, Garmin has not yet enabled Garmin Pay on the FR645. That date is currently set for March 19th, about two weeks from now.  I’ll circle back and update this review with how it functions once they’ve released it.

Of course, I don’t really expect it to be any different than the Vivoactive 3 that was released this past fall.  Everything I can see from toying with things on a beta build is identical to that of the Vivoactive 3.  You load your credit card via the Garmin Connect Mobile app onto the watch, it does some approval magic behind the scenes, and then you can use your watch to tap and pay for things without issue.

By and large it works great on the Vivoactive 3. And while I’d never say something ‘will absolutely work the same’ on a different product, I’ve got pretty high confidence you’ll see virtually no difference here.

Of course, that’s not really the issue with Garmin Pay.  Rather, the challenge is simply whether or not your bank is supported.  Certainly Garmin has added a pile of banks since last fall with the Vivoactive 3 launch, but they’re still missing key banks, especially in the US with lacking Chase (who dominates the credit card industry).  Not to mention banks overseas.  Garmin is ultimately in the same position as Fitbit is right now, in that they have to individually negotiate and onboard every bank on the planet.  This took Apple years to do, and even then not every bank is supported.

Unfortunately the nature of how this portion of the industry works really does require each bank to be individually onboarded. There is no easy button, as they aren’t just enabling all Visa or Mastercard cards in one easy shot.

In any case, if you want to see how it works on the Vivoactive 3 – hit up my video here on it.

GPS Accuracy:


There’s likely no topic that stirs as much discussion and passion as GPS accuracy.  A watch could fall apart and give you dire electrical shocks while doing so, but if it shows you on the wrong side of the road?  Oh hell no, bring on the fury of the internet!

GPS accuracy can be looked at in a number of different ways, but I prefer to look at it using a number of devices in real-world scenarios across a vast number of activities.  I use 2-6 other devices at once, trying to get a clear picture of how a given set of devices handles conditions on a certain day.  Conditions include everything from tree/building cover to weather.

Over the years I’ve continued to tweak my GPS testing methodology.  For example, I try to not place two units next to each other on my wrists, as that can impact signal. If I do so, I’ll put a thin fabric spacer of about 1”/3cm between them (I didn’t do that on any of my FR645 workouts).  But often I’ll simply carry other units by the straps, or attach them to the shoulder straps of my hydration backpack.  Plus, wearing multiple watches on the same wrist is well known to impact optical HR accuracy.

Next, as noted, I use just my daily training routes.  Using a single route over and over again isn’t really indicative of real-world conditions, it’s just indicative of one trail.  The workouts you see here are just my normal daily workouts.

I’ve had quite a bit of variety of terrain within the time period FR645 testing.  This has included runs in: Paris, Amsterdam, Las Vegas, Adelaide, Perth, and plenty more.  Cities and countryside, trees and open-air. It’s been everywhere!

First up we’ll start with something relatively easy – a run that’s mostly open-air with a bit of trees or small buildings nearby, but nothing complex. It’s always a good starting point.  This beach and then river path is well travelled by runners in the area. Here’s the GPS tracks comparing the Garmin FR645, Suunto Spartan Trainer, FR935, and FR630. This gives you a bit of perspective looking back at the FR645’s older sibling, the FR630. Here’s the DCR Analyzer file set if you want to poke around yourself.


Of course, at this super high-level view you can only see that nobody went totally wonky, so let’s dig in a bit closer and try and find some challenging spots.

The beginning/ending is actually kinda fun, as it’s a small path that swerves back and forth for no apparent logical reason. In this case, you’re seeing both the end and the start of the run shown, but as you can see, all of the units agree very nicely here. They’re all within a meter of the path at worst, if not just straight on the path.


Next, for the following few miles, things look pretty solid. If I wanted to get all nitpicky I’d note that both the older FR630 and the Spartan Trainer on the outbound only seemed to be offset by about 2 meters, into the parking spaces. This only occurred in one direction, and on both those units only.  No idea why.


Next, at the turnaround point, you’ll see that I follow the edge of a building. Only the FR645 nailed this corner properly, the rest seemed to go inside what I think is a pub. Fair enough, it was 9PM on a Saturday night.


Of course, give some, take some.  A bit later on the way back the FR645 went bar hoping itself, while the other units were all roughly correct.  The impact on distance from this excursion is still pretty darn minor.


Finally, if we look at the total distance written to the files, you’ll see that they’re all within 100m of the FR645  (which sits precisely in the middle of them), on what is a 13KM run. That puts the total spread at basically 0.7%, which seems respectable enough to me (since we already evaluated the actual tracks separately).


Next, let’s head into the bush on a bit of a run that has mixed tree cover and some open areas. Here’s what it looks like:

2018-03-03 12.45.32

And here’s the track files (FR645/Suunto Spartan Trainer/FR935), and here’s the DCR Analyzer set.


It kinda goes without saying that there’s virtually perfect alignment between these units on this route. Somewhat impressive actually. Scrolling all the way around the entire lake, about the only point I can find a bit of disparity on is this little section here, with the FR935. But given I was hand-holding that next to a GoPro, it’s entirely possible the unit was occasionally covered up there – blocking signal. And even then, the difference is very minor.


Looking at the rest of the track is kinda silly, since it’s so identical to be a non-event. Now oddly, here’s the distance totals:


It’d mildly interesting to see the FR935 at about a 200m loss compared to the other two, since it shows a virtually identical track and didn’t have any other sensors (like a footpod) overriding distance.

Even if I go all the way back to January on GPS accuracy, I’m not seeing any appreciable difference here in GPS accuracy for running.  Also, in the HR section all of those sets (some of which are different from these here) all show essentially the same thing: It matches virtually perfectly with other units.

Switching gears for a moment, let’s look at a ride – this one across half the city and back again with plenty of opportunity for challenging GPS moments. Here’s the super-duper high level (and the DCR Analyzer Link):


Now, before we get started, I want to point out one interesting tidbit.  About two miles into the ride I headed into a bike shop to get a part swapped out.  I did NOT stop any of the GPS units. It’s a couple story concrete building, definitely not a little wooden shack. It’s here that the FR645 plotted some rather excited GPS tracks. The other units were a bit more clustered.  Obviously, this isn’t really something I can truly complain about – but I wanted to call it out in case folks were digging into the files and wondered what on earth exploded there.


In any case, as soon as I went back outside the tracks were perfect virtually instantly.  You can see this intersection that I went in/out of at different points in the ride.  All the units were so tightly clustered together it’s astounding. They’re even showing me properly in the bike lane and all.


Next, I zoomed all the way around the river trying to find a spot where any of the GPS units disagreed, but frankly, that just never happened.  Even passing under an 8-lane highway at low-speeds, they all were clustered within a few meters of each other.


Basically, all the way around, it just looks like a nice little peloton of perfection riding together:



Ultimately, I’m not seeing any appreciable GPS accuracy issues (aside from me being stupid and leaving the watch running indoors), across either running or cycling (or hiking/walks), which are the main GPS-driven activities on the FR645.

(Note: All of the charts you see in this review are created using the DCR Analyzer.  You can also use it as well to create/share your own comparisons between multiple devices/sensors/etc, more information here.)

Heart Rate Accuracy:


Next up we’ve got heart rate accuracy.  This roughly falls into two buckets: 24×7 HR, and workout HR.  As is usually the case with most devices these days, I see no tangible issues with 24×7 HR.  It works well across both normal daily routines as well as things like sleep.  Speaking of which, I talk about RHR values and 24×7 monitoring here and why it’s interesting.

2018-03-06 13.19.32 2018-03-06 13.15.43

Before we move on to the test results, note that optical HR sensor accuracy is rather varied from individual to individual.  Aspects such as skin color, hair density, and position can impact accuracy.  Position, and how the band is worn, are *the most important* pieces.  A unit with an optical HR sensor should be snug.  It doesn’t need to leave marks, but you shouldn’t be able to slide a finger under the band (at least during workouts).  You can wear it a tiny bit looser the rest of the day.

Ok, so in my testing, I simply use the watch throughout my normal workouts.  Those workouts include a wide variety of intensities and conditions, making them great for accuracy testing.  I’ve got steady runs, interval workouts on both bike and running, as well as tempo runs and rides – and even running up and down a mountain.

For each test, I’m wearing additional devices, usually 3-4 in total, which capture data from other sensors.  Typically I’d wear a chest strap (usually the HRM-TRI or Wahoo TICKR X, but also the Polar H7), as well as another optical HR sensor watch on the other wrist (many models during this testing period including the Wahoo TICKR FIT, Polar OH-1, a prototype Scosche Rhythm 24, and Scosche Rhythm+).  Note that the numbers you see in the upper right corner are *not* the averages, but rather just the exact point my mouse is sitting over.  Note all this data is analyzed using the DCR Analyzer, details here.

Note that while I’ve been using the FR645 since December, I’m mostly going to use recent data in this review – since that’s the firmware that it’s currently on and the production firmware that real world people are using.

First up we’ve got my evening run from the other night, which is more of a steady-state run.  Still, it’s always a good place to start before we get into more complex things. In this case I was comparing the following HR sensors: FR645 Optical, Polar H7 Chest Strap, Scosche Rhythm 24 (Prototype device), and Suunto Spartan Trainer Optical.  The DCR Analyzer set data is here.


What you see is that on the whole, things are virtually identical between them.  You do see a few weird moments here and there on the other sensors.  For example a couple of random bumps on the Suunto Trainer optical sensor.  And you see two brief moments where the Polar H7 has a small blip. I didn’t do anything notably different at any point on this run, except the 26 minute marker where you see that dip and I took a photo standing on a bridge.


But otherwise, it’s pretty darn consistent.  If we look at the very very start of the run, we see slightly different ramp rates, which is pretty common for any heart rate sensors to agree on dramatic shifts in heart rate. I’m actually surprised they were as close as they were during that ramp and that they all got to basically the same point within about 70 seconds (usually I see closer to 3-4 minutes).


All in all, nothing terribly exciting (good or bad) on that set. The FR645 performs exactly as it should.  All of my steady-state runs over the last nearly three months are pretty much just like this – non-events that just do what it should.

So let’s kick it up a notch and get a bit more complex. This next run was relatively steady pacing on the outbound, but then on the return I decided to mix it up a bit with some fartlek’s of sorts, which basically means variable distance/time intervals and variable pacing.

Here’s the the overview of that magical run.  In this case I’m comparing the FR645 optical with the Wahoo TICKR-X chest strap, and the Scosche 24 optical HR sensor (prototype device). Here’s the DCR Analyzer set.


As you can see, things got off to a pretty awesome start…with approximately none of them agreeing for the first 3 minutes, and in this case in a horribly bad way.  But the correct HR track is easy to spot – it’s the FR645.


The reason we know this?  Well, it’s unlikely I’m running at a 7:00/mile with a HR at 80bpm.  So that means the Scosche is out.  And then it’s equally unlikely I’m peaking at 176BPM in the first four minutes at that pace.  Instead, you can see the gradual and correct HR plot of the FR645 as I built into things.

Next, for the following 20 minutes or so I was relatively constant in pace, and while we see some slight disagreement between the units (primarily from the Scosche), they’re all within about a 3-5bpm spread (or less).  That dip there is where I stopped to take a photo at a lighthouse for about a minute.


After this point I start varying my pace/intensity as well as the durations, mostly aligned to random railroad crossings.  And this is where things start to get a wee bit messy. I’d say the prototype Scosche is the least certain as to what’s going on here.  That leaves us with the TICKR-X and the FR645 optical to evaluate.


For the build portion of almost each ‘interval’, the FR645 actually nails it quite well.  But you’ll see that on the first recovery portion, the FR645 lags a bit.  The second the FR645 is probably the most correct, as the TICKR-X incorrectly spikes.  Then the 3rd interval the TICKR-X and FR645 agree happily, even into the 4th interval as well.  But the 5th interval the FR645 seems to totally miss that I started running hard again.

Ultimately for that specific run it wasn’t horrible, but just not perfect either.

Next, let’s kick up the difficulty level one more time. We’ll go to a run I just did this morning, a simple interval run (using the built-in interval feature no less). 6x400m, with 90-seconds rest.  Also, I did about a 12 minute warm-up, and then some cool-down as well.  In this case I was comparing against the prototype Scosche 24, the Polar H7, and Suunto Trainer optical and the FR645 optical. Here’s the overview and the DCR Analyzer data sets.


Huh. Well then. So, skipping right to the meat of things – the first 13 minutes (warm-up + rest) were spot-on between all of them. Simple goodness.

But then the intervals got a bit messy, primarily from the FR645.  It actually did fairly well for the build portion of each interval (save the first one), but would totally lose the plot on the rest portion of each interval.  For this run I was just walking for the recovery portion, carrying no cameras.

There’s honestly not much more to say here, the recovery completely misses the boat…every single time.


So this got me curious a bit – was this a one-off, or something more common.  So I dug back through my January files, and in most cases there it did fairly well on recovery.  I then went through February, and that too was fine.  In fact, here’s a workout I did using the FR645 while pushing a stroller and running outside on Zwift (and filming all at once).  And the FR645 did great on those intervals. Analyzer here.


So I’m not entirely sure about this morning. One interesting thing that I did differently today was add in the RD-Pod. I note this because I actually haven’t used that since January or so. But I remembered back to a beta issue I had seen where the RD pod was causing weird HR data.  When I removed the RD pod, that went away.

Why would that matter you ask? Well, the RD pod is used as a cadence source when connected, because in theory the cadence data from it is higher quality than wrist data (since it wouldn’t be impacted by things like taking a drink of water or what-not).  But in looking at my cadence data from today’s run, via the RD-Pod, it looks all dorky when I’m walking.  You can see how incredibly variable it is, compared to when I’m running it’s rather clean. Makes me wonder if perhaps my RD pod is having issues in certain scenarios.


Now, this is just a wild-assed guess, and if it wasn’t already super-hot outside and that I’ve got other things to do I might re-do the run without it.  But, it’s a production product at this point so fair is fair.

Ok, switching gears a bit – let’s look at cycling and the HR there. Historically speaking things aren’t usually terribly awesome with the Garmin ELEVATE sensors and cycling, especially when variability is in question.

Below is a two hour ride with mostly consistent riding in the middle section, but a bit more variability towards the second half.  The first portion there with the yellow underline is where I was in the bike shop that I mentioned above.  So let’s not give it too much grief there since I was actively trying to fix a bike with the mechanic.


Instead, let’s focus on the rest of the ride. In this case I had apparently connected 3 other head units to the same heart rate strap…so we’ve only got one data point to compare against.


Still, what you see is that all the way up till about the 1hr 40min marker things are remarkably close.  There’s one point where it briefly seems to lose the plot during recovery, but actually better overall than I expected.

After that point though there’s a ton more variability and it just doesn’t match at all – including one 200BPM spike that clearly isn’t correct.  What you see in that last portion is what I typically see for wrist optical HR sensors while riding. It’s where I was stopping and starting at various lights, and thus lots of stop and go.  Whereas when I was riding more steady-state, it’s all good.

So what’s my overall opinion on the FR645 optical HR sensor?  Well, obviously it’s mixed.  As usual, it’s not terribly awesome for cycling if you’re doing any shifting in intensity or stops/starts.  When it comes to running though, for steady-state it’s perfectly fine, no issues there.  But for intervals it seems a bit mixed.  You saw on that fartlek run that it was largely pretty good, minus a few quirks.  Whereas this morning it completely crapped itself on recovery.  It’s unclear though if something large is at play with the RD-Pod, since my other interval runs were just fine.

I’m going to keep on chugging with it and report back in a month or so – but at this point I’ve got 3 months of good data, and none anywhere near what I saw on this single run this morning.  Sometimes it’s just bad luck for a product when it comes to reviews and the timing of any given random workout.

Product Comparison:

You’ll find the FR645 has been added to the product comparison database, which allows you to compare it to a boatload of other products I’ve reviewed.  For the moment, I’ve compared it to the Polar M600 (has music and running focused), the Apple Watch (has music and running features), and the FR935 (multisport, so you can see the differences – no music). Of course, you can make your own comparisons against any other watches here within the product comparison calculator.

Function/FeatureApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Copyright DC Rainmaker - Updated March 6th, 2018 @ 9:32 amNew Window
Price$329/$399 (cellular)$399/$449 (with music)$499$329
Product Announcement DateSept 12th, 2017Jan 8th, 2018Mar 29th, 2017Aug 3rd, 2016
Actual Availability/Shipping DateSept 22nd, 2017Late January 2018Mar 29th, 2017Sept 2016
GPS Recording FunctionalityYesYesYesYes
Data TransferBluetooth SmartUSB/Bluetooth Smart/WiFiUSB/Bluetooth Smart/WiFiUSB/Bluetooth Smart/WiFi
Waterproofing50mYes - 50mYes - 50mIPX8 (good for swimming)
Battery Life (GPS)5hrs GPS on time (24-48hrs standby)14hrs GPS/5hrs GPS-MusicUp to 24hrs in GPS-on, up to 50hrs in UltraTrac GPS10 hours
Recording IntervalVaries1S or Smart1S or Smart1-second
Satellite Pre-Loading via ComputerYes (but seems questionable)YesYesYes
Quick Satellite ReceptionNot generallyGreatGreatGreat
Backlight GreatnessGreatGreatGreatGreat
Ability to download custom apps to unit/deviceYesYesYesYes (Android Wear)
Acts as daily activity monitor (steps, etc...)YesYEsYesYes
Can control phone musicYesYesYEsYes
Has music storage and playbackYesYes (3.5GB)NoYes
ConnectivityApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Bluetooth Legacy (pre-4.0) to PhoneNoNoNoNo
Bluetooth Smart (4.0+) to Phone UploadingYesYesYEsYes
Phone Notifications to unit (i.e. texts/calls/etc...)YesYesYesYes
Live Tracking (streaming location to website)With 3rd party appsYesYesWith some apps
Group trackingNoYesYesNo
Emergency/SOS Message Notification (from watch to contacts)YesNoNoNo
Built-in cellular chip (no phone required)Yes (with cellular version)NoNoNo
CyclingApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Designed for cyclingYesYesYesYes
Power Meter CapableNoNoYEsNo
Power Meter Configuration/Calibration OptionsN/AN/AYesN/A
Speed/Cadence Sensor CapableNoYesYEsNo
Strava segments live on deviceNoYesYesWith Strava app
Crash detectionNoNoNoNo
RunningApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Designed for runningYesYesYesYes
Footpod Capable (For treadmills)With 3rd party appsYesYEsNO, HAS INTERNAL ACCELEROMETER
Running Dynamics (vertical oscillation, ground contact time, etc...)NoWITH RD POD, HRM-TRI OR HRM-RUN (NOT VIA OPTICAL HR)WITH RD POD, HRM-TRI OR HRM-RUN (NOT VIA OPTICAL HR)No
VO2Max EstimationYesYEsYesNo
Race PredictorNoYesYesNo
Recovery AdvisorNoYEsYEsYes
Run/Walk ModeWith 3rd party appsYesYesNo
SwimmingApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Designed for swimmingYesYesYEsYes
Openwater swimming modeYEsNoYesNo
Lap/Indoor Distance TrackingYesYesYesYes
Record HR underwaterYesNoWITH HRM-TRI/HRM-SWIM (Not with optical HR)Yes
Openwater Metrics (Stroke/etc.)Basic stroke type onlyNoYesN/A
Indoor Metrics (Stroke/etc.)Basic stroke type onlyYesYesN/A
Indoor Drill ModeNoYesYesNo
Indoor auto-pause featureYesNo (it'll show rest time afterwards though)No (it'll show rest time afterwards though)No
Change pool sizeYesYEsYEsYes
Indoor Min/Max Pool Lengths1y/m to 1,500y/m+17M/18Y TO 150M/Y17M/18Y TO 150M/Y
Ability to customize data fieldsVery limitedYEsYesYes
Can change yards to metersYesYesYEsYes
Captures per length data - indoorsYesYesYesYes
Indoor AlertsYes (goals)YesYes
TriathlonApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Designed for triathlonNot reallyNoYesNo
Multisport modeYesNoYesNo
WorkoutsApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Create/Follow custom workoutsWith 3rd party appsYesYesYes
On-unit interval FeatureWith 3rd party appsYEsYEsNo
Training Calendar FunctionalityWith 3rd party appsYEsYesYes
FunctionsApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Auto Start/StopYesYEsYEsNo
Virtual Partner FeatureNoYEsYEsNo
Virtual Racer FeatureNoYesYesNo
Records PR's - Personal Records (diff than history)NoYesYEsNo
Day to day watch abilityYesYesYesYes
Hunting/Fishing/Ocean DataNoNoYesNo
Tidal Tables (Tide Information)NoNoNoNo
Jumpmaster mode (Parachuting)NoNoYesNo
GeocachingNoNoVia GPS coordinatesNo
Weather Display (live data)YesYesYesYes
NavigateApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Follow GPS Track (Courses/Waypoints)With 3rd party appsYesYesNo
Markers/Waypoint DirectionWith 3rd party appsYesYEsNo
Routable/Visual Maps (like car GPS)With 3rd party appsNoNoNo
Back to startWith 3rd party appsYesYesNo
Impromptu Round Trip Route CreationWith 3rd party appsNoNoNo
Download courses/routes from phone to unitWith 3rd party appsYesYesNo
SensorsApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Altimeter TypeBarometricBarometricBarometricGPS
Compass TypeN/AMagneticN/A
Optical Heart Rate Sensor internallyYesYesYesYes
Heart Rate Strap CompatibleYesYesYesYES - CONTAINS OPTICAL HR SENSOR
ANT+ Heart Rate Strap CapableNoYEsYesNo
ANT+ Speed/Cadence CapablenoYEsYesNo
ANT+ Footpod CapableNoYEsYesNo
ANT+ Power Meter CapableNoNoYesNo
ANT+ Weight Scale CapableNoNoNoNo
ANT+ Fitness Equipment (Gym)NoNoNoNo
ANT+ Lighting ControlNoYesYesNo
ANT+ Bike Radar IntegrationNoYesYesNo
ANT+ Trainer Control (FE-C)NoNoNoNO
ANT+ Remote ControlNoNoNo (can control VIRB though)No
ANT+ eBike CompatibilityNoNoNoNo
ANT+ Muscle Oxygen (i.e. Moxy/BSX)NoYesYesNo
ANT+ Gear Shifting (i.e. SRAM ETAP)NoNoYEsNo
Shimano Di2 ShiftingNoNoYEsNo
Bluetooth Smart HR Strap CapableYesYesYesYes
Bluetooth Smart Speed/Cadence CapableNoYesYEsNo
Bluetooth Smart Footpod CapableNoYesYEsNo
Bluetooth Smart Power Meter CapableNoNQoYEsNo
Temp Recording (internal sensor)NoYesYEsNo
Temp Recording (external sensor)NoYesYesNo
Compatible with Firstbeat HR toolsNoN/AYEsN/A
SoftwareApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
PC ApplicationNonePC/MacGarmin ExpressNo
Web ApplicationNoneGarmin ConnectGarmin ConnectPolar Flow
Phone AppiOS onlyiOS/Android/Windows PhoneiOS/Android/Windows PhonePolar Flow (iOS/Android)
Ability to Export SettingsNoNoNoNo
PurchaseApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Amazon LinkLinkLinkLinkLink
Clever Training - Save a bunch with Clever Training VIP programN/ALinkLinkLink
Clever Training - Save a bunch with Clever Training VIP programN/ALinkLinkLink
DCRainmakerApple Watch Series 3Garmin Forerunner 645Garmin Forerunner 935Polar M600
Review LinkLinkLinkLinkLink

And don’t forget – you can make your own product comparison here within the product comparison charts!



So what’s the wrap-up on Garmin’s first music enabled watch?

Honestly, it’s probably too soon to tell.  Sure, from a pure non-music running standpoint it’s more or less the same as the Garmin Forerunner 935 or Fenix 5 series. There’s virtually no differences there.  So if you were looking for a cheaper FR935 for just running purposes (and the occasional pool swim), then this is probably your best bet since it’s $100 less sans-music. Not to mention the upcoming integration of the FirstBeat driven metrics across Garmin’s newer devices, will be appealing to those that want the advanced training and load status across both their cycling and running devices independently.  And of course, there’s Connect IQ – which continues to grow and has boatloads of apps and watch faces that are very endurance sports focused (and even Uber). It won’t have the more mainstream apps you’d find on an Apple Watch, but for the athlete it seems to do the trick.

Shifting focus, once you get into the music realm, the jury is somewhat out depending on how you typically listen to music.  For me personally, I’m more about streaming services.  And in Garmin’s case, even once iHeartRadio comes online in the next week or two, that won’t really solve my problem because it’s not a platform I use and it’s not a platform available to me outside the US.  Deezer might solve my problems (despite me not using it), but that’s realistically probably two months away, assuming no further delays.  I also think that we’re probably going to see a lot of folks realize just how finicky Bluetooth audio headphones are when connected to watches (as has been the case for years).  Garmin will likely catch some flak there, even when not entirely deserved (perhaps they should have followed Fitbit’s lead in making their own headphones that were guaranteed to work).

Still, for a lot of people this watch will hit its mark, and especially do so over time as Garmin matures its music offerings.  It’s finally getting the pieces in place for Garmin to eventually be able to compete in the core feature checklist of having music.  Undoubtedly we’ll see them eventually bridge the music portion to other devices, it’s most just a matter of when.

With that – thanks for reading!

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Garmin Forerunner 645 (select dropdown for different colors/variants)
Garmin Forerunner 645 – European readers

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Thanks for reading! And as always, feel free to post comments or questions in the comments section below, I’ll be happy to try and answer them as quickly as possible.

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  1. It’s great that the 645 supports the Garmin Runnig Power app

    • Freek

      Is it likely that there Will be a software update to use running power in a broader way? For example to use power zones in interval training and in a data field (minutes in each zone)?

      For a running oriented watch currently it does not have any running features not already offered by 935, f5,f5s,f5x or my Chronos.

      Be nice to expand the abiliti3s of Garmin and stryd power.


  2. Walter Guerra


    What about that idea that Garmin talked about after releasing the Fenix 5 (I think), that all devices will use the same charging cable? I think only the Fenix series/935 uses that cable now, right?


    • It sounds like it was driven by basically space constraints, if you read between the lines of this exchange about it:

      “The decision to use the standard “clip” charger for Forerunner 645 was primarily driven by the fact that it worked better in our physical design to keep the product size down where it is.”

      I suppose I look at the positive side: At least it’s roughly the same charging cable as other watches, and not some new totally different thing.

    • Actually, the Vivoactive 3 also use this “standard” cable. Maybe a different team was developping the 645 and started to work on the old design, before the “gosh, it’s too late to put the new connector of the other team…”. :-)

  3. hudo

    Any insights some of these functionalities would land in Fenix 5 series land ?

    – NFC payments: do Fenix 5 series have NFC chip? I doubt it.
    – Bluetooth music player: I think Fenix 5 series currently doesn’t have compliant BT protocol stack/protocol but maybe Fenix 5X could do that.
    – Responding to messages from watch itself via predefined message texts. I think this could definitely be done via firmware update to Fenix 5 series ! I am not sure do 645 reponds via SMS only or it can respond natively in message format it received the message in the first place.

    Please comment on these ! Thanks!

  4. Martijn Smale

    Hi Rainmaker,

    Thanks for you extended comprehensive review! Currently I am using a forerunner 630, do you think it would be worth the upgrade when you look at the extra functionalities of a 645 (non-music) ?

    I am thinking of buying the 645 on a short notice, but I am curious about the extra functionalities it has. Garmin Pay will not be available in the Netherlands on the short term. And as you said it has some flaws in the optical heart rate while doing interval trainings. Taking this in consideration, my chest strap still works fine!

    Looking forward to your reply.

    Thanks in advance!

    Kind Regards,

    Martijn Smale

    • It’s funny, in doing random sporadic runs with the FR630 and FR645 almost side by side (like this morning, last weekend, and so on), I’ve come to realize how big a jump it is.

      It’s kinda like the whole lobster pot thing, when you’re slow boiled over a couple of years, it seems perfectly fine. But man, the number of times I wanted to throw that FR630 and its wonky-ass touch-screen at a passing bus would probably astound you. Which is funny, because a few years ago I used it as a daily running watch without any issues.

    • Joop Verdoorn

      I have both the FR935 and the FR630. The FR935 doesn’t feel like a big upgrade personally. Biggest difference is the battery time,which surprises me still, but the FR645 doesn’t excel there. The CIQ 2.0 capabilities (32kb datafields) do matter in my opinion, as the FR630 cannot have the nice datafields the FR645 can have (like my Datarun plus datafield, which requires the full 32kb).

    • ekutter

      I too have both. When I upgraded to the 935, one of the biggest draw backs for me was no touch screen. After using the 935 for about a year, I have to agree with Ray. The pure button interface is so much better in so many situations. One of the biggest is the screen stays way cleaner without constantly putting my grimy fingers on it. Lately I’ve been doing a lot of outings exploring new areas and having the full course support has also been huge. No longer do I need to carry my Edge with me. One big bummer for me (but wasn’t supported on the 630 anyways) is I can’t get the OHR to give me reasonable consistent numbers for anything.

  5. Greg

    Hi DCR, great review as always thanks.

    Can you elaborate more on the loading of local music onto the device, especially when it comes to playlists or do playlists only work from streaming services? Does it recognise m3u playlists for example?

  6. Fun nerdy fact, 4GB (4000000000 Bytes) is 3.72 GiB (4 * 1024*1024*1024 Bytes). This is also the reason your hard drive appears smaller after formatting since disk manufacturers always use decimal and operating systems usually use binary measurements.

    Re the “pink” strap I actually wish Garmin offered more bright colours and would hapily wear a Cerise strap with my F5 if it were available in a mens size. Unfortunately Garmin live in “men want black, large and dull things and women want pink, small and bright things” Kansas and have yet to realise that tastes differ accross the world and that they are selling to a global market. All of the F5 straps are dull versions of the colours, even the “amp yellow” is the dullest yellow I’ve ever seen!

    • JR

      Fortunately these are standard quick release straps, so you have a staggering number of third party options that are also much cheaper. I’m partial to Clockwork Synergy’s cordura bands.

  7. Josh

    Non music Black strap or sandstone strap…hmmm

    • RTellis

      I went with the sandstone. But then I already have a VA3 with the black band I can swap onto the 645 when I want.

    • RTellis

      Update: Received mine yesterday and the strap isn’t nearly as tan looking as the photos. It’s a much lighter shade almost like a tinted putty color.

      Not horrible, but not nearly as good as I was hoping for.

  8. Adam

    Hi Ray,

    What is the final version of the 645 that you are using? 2.4?

  9. Rob

    I have a question on playing music: Does it remember where the music stopped and continue to play from that point when you use the music again? I tend to listen to long remixes and i don’t want it to start at the beginning every time..

  10. Justin

    Thanks Ray,

    This watch is replacing my buggered fr220 which I have loved using. I’ve never listened to any music when running before, but might give it a go listening to podcasts and such now.

    To get the most out of the watch should I be wearing a HRM-Run strap or RD-pod when running? I’m going to grab one of them. It was going to be the RD-pod but post your review I’m not sure.

    Cheers, and glad you have enjoyed your time in Australia

    • I’ve historically had no issues with the RD Pod. I’ll be circling back to Garmin again to see if we can figure out what’s up, and whether it was generally poor optical HR tracking, or RD Pod driven. In the past they were able to use the data from my .FIT files to see exactly where the source of the failure was.

      My .FIT files from that run are downloadable in the file set linked above, so perhaps they’re already cookin’ on it (I haven’t circle back to them on this mornings run, since it was around 1AM their time by time I analyzed it).

    • Justin

      Be interesting to here from Garmin on it.

      I’ll most likely go with the RD Pod if I get curious about the extra data it can provide, I really don’t want to go back to HR straps after using my Rhythm+ when I’ve wanted HR data from my old fr220.


    • Dennis Piche

      Just picked up the RD pod so I am interested to hear what you find out.

  11. Kai B

    Any connectivity issues like with Fenix 5?
    Is it possible to control music (skip/play/pause) by the BT earphones?

    • Garmin-Joey

      The Forerunner 645 Music has been designed to support standard Bluetooth protocols for wirelessly playing music, however there are differences in performance between different headphones and headphone manufacturers. While it is possible that the headphone controls would be able to control the music on the watch due to differences in headphone manufacturers it is difficult to say if all headphone controls will work.

      The headphones that I use (Jabra Step Wireless) the headphone controls work as expected to control the music on the watch

    • Tonny Joost

      I use the Jabra Elite Sport BT – and they work perfect with BT handling play/pause, volume etc.

  12. Andrew

    Thanks Ray!

    Is it confirmed that Non Music 645 actually has 2 hrs Longer gps battery life?

    • Morgan McGuire

      Also curious about this. I got the 645m even though I will never use the music feature, just because it was available first. Will I have less potential battery life simply due to having the music model, even if I don’t use that feature? If so, I think I’ll switch to the base model. Thanks for any info/help!

    • Garmin-Joey

      Page 24 in the PDF manual gives a breakdown of the expected battery life for both Forerunner 645 and 645 Music in various use cases.

      link to static.garmin.com

      Using the Forerunner 645M with GPS and no music you can expect to get up to 14 hours of battery life.

    • Andrew

      Thank you,

      Initially the product page listed the 645M as 14 and the 645 as 16. But this seems to have been fixed.

  13. Sam B

    Thanks for a comprehensive review! Is the Garmin 935 more accurate concerning the wrist HR, overall and at intervals, than the 645? Aren’t they both using the same elevate hr sensors? How do they both compare as far as hr accuracy to the polar m430? Additionally, in your comparison you noted that 645 doesn’t have the “back to start” feature. Doesn’t it have breadcrumbs? What’s missing as far as “back to start” in comparison to the 935? Also, does it have the same compass as the 935? I noticed in your comparison a magnetic compass on the 935. Thank you! Keep up the good work!

    • I’ve found the M430 optical HR very very good. The thing is that this watch and that watch overlap in terms of core running features, but less so for things like music, apps, contactless payments, etc…

      I think by and large the optical sensor accuracy is a wash between the FR935 and FR645. I suspect any differences I see are mostly just dumb-luck as to why it works better on one given day/run than another.

      The FR645 has a magnetic compass (and just re-validated that sitting here inside without GPS no less, when I orient the watch southwards, it shows roughly 180*.)

      Note: Fixed the back to start error in the table. Sorry!

    • Sandro

      Nice that it has a magnetic compass! Is it leveraged when following courses (showing also the direction from the compass)?

  14. Ian Marchant

    Minor error I believe in that you say Garmin Pay goes live on March 19th which is 2 weeks ago.

    In other news, I now have a new object of desire to try and persuade the better half to let me have :-)

    • I’m so confused. In Australia, it’s still March 6th (for 21 more minutes anyway). Is it April in the UK?

    • Paul S

      I was confused at first, too, but he’s just quoting your text back at you, and pointing out the error. But Ray, if you really are in April, could you fill out our NCAA brackets :-)

    • Durrrr… I get it now.

      I read it like 6 times over and still didn’t get it. Now I get it, it’s the ‘ago’ part. Sorry, I thought he was saying I had typed it in February or something. Thanks!

    • Ian Marchant


      Maybe my brain is working differently today. I meant to put quotes round it and then just… didn’t

      I blame the children!

    • Eni

      …don’t we all? (blame the children, I mean :-D )

    • Ian Marchant

      If there is any way to blame them then go for it :-)

      These newer watches look to be so far ahead of my 610 that I may have to upgrade soon. Wonder if the kids will mind missing out on school trips for a while ;-)

  15. Rob

    Hi Ray, any ant+ issues with stryd?

    • I haven’t re-tested with Stryd in the last week, but I didn’t see any Stryd droppage issues back at while ago using a side-loaded version. I’ve gotta re-add it in and see if anything shows up.

      (I was having Stryd charging issues during my trip using a 3rd party wireless charger I had brought to also charge my phone, but just got a new wireless charger last week and all is happy now).

  16. LF

    Clever Training UK just sent me an e-mail saying they have shipped 645 base version (no music). Wasn’t expecting so early in the month now.

  17. TC

    Seems odd that they make it pool swimming compatible but do not support HRM-TRI / HRM-SWIM swimming HR.

    • Yeah, it wasn’t on the Vivoactive series either, despite supporting indoor swimming. I kinda agree, never really made sense to me since the HR strap was an easy upsell for them.

  18. Chris

    amazon music support would totally rock – as it stands, I guess I continue carrying my phone on runs.

    • Garmin-Joey

      Garmin is actively working to bring music service providers iHeartRadio and Deezer to the Forerunner 645M. When available these services will be enabled through a download from the CIQ App Store. Garmin continues to explore expanding this offering by including CIQ applications from other music service providers.

    • Gizero

      Spotify is pretty much the only streaming music service that matters in Europe. There appears to be no near-future plans to support that on the 645 Music, so I’ll get the standard version instead and save a few bucks.

    • Michael

      It’s fairly easy to migrate existing playlists from Spotify to Deezer. I will definitely change my accounts, when a direct streaming download from Deezer is possible.

    • PeterF

      Personally, I’m a big fan of di.fm And I guess that’s part of the problem: N customers, N+1 services being asked for…

      And thinking a bit more about it, I don’t think streaming music has a place on a watch. Unless it natively supports 4G that is. If I need my mobile to provide a wifi-4G bridge anyway, then why not just use the phone for streaming? The appeal of such these watches is that you can leave that clumsy phone at home!

    • A number of watches have built-in cellular today. Including the Apple Watches and a bunch of Android Watches.

      The appeal of streaming services for non-cellular watches is that the music is dynamically updated when you sync to specific playlists that you’ve favorited (that in turn usually change daily/weekly/etc…). As such, you don’t end up with this random set of static MP3 files on your watch that never change.

    • Kerri Muldowney

      I only use Amazon music so if/when Garmin uses it my running will be complete 😍

  19. Michael R.

    Can you elaborate on why the lactate threshold function requires a separate chest strap? I’m not sure I follow. Does an external optical HRM provide the same data (e.g., Scosche)?

    “Note that the lactate threshold function (either the manual guided test or the automatic recognition) requires a chest strap, as that’s currently the only way to get HRV/RR data while in a workout.

    • Garmin-Joey

      A chest strap is needed because the optical heart rate sensor is not able to accurately measure HRV (heart rate variability, which is the changes in the interval between heartbeats.

      To get an accurate lactate threshold the watch needs to be able to get the HRV data and wearing an HRM will allow that data to be recorded.

      More information about lactate threshold and other Physiological Measurements can be found at link to garmin.com.

  20. Piotr

    Thanks for the review.

    I noticed in the DCR Analyzer graphs that your elevation on 645 is 400-500 feet more than all other devices. Is that because altimeter wasn’t calibrated to your current location? I see that changes in elevation in 645 mimic other devices so that’s good to see.


    • It’s funny, I noticed the elevation gap when I was editing a photo this evening, that it was showing a rather high elevation given my elevation here near the beach is like 5 meters or something.

      As you noted, the elevation ascent/descent is perfect compared to the others, but the baseline seems offset. Best I can tell there’s no method to re-calibrate the elevation to another value. I’ll circle back to Garmin and see if they have any ideas or tips.

    • Piotr

      Thank you very much. It would be great to hear what they have to say about that.

      Ascent/descent is much more important but it would also be good to know that the hill I just climbed is 1000 ft above sea level and not 1500 ft; even though 1500 ft looks more impressive.

      Thanks again.

    • Jon

      Noticed this on mine this morning too: came here looking to see if anyone had found where to recalibrate the Baro – apparently not yet!!

    • I chatted with Garmin about this, it sounds like they’ve tracked down what’s going on and that I should see if the condition persists after the next firmware update (I don’t have a timeframe for when that is, but typically they iterate pretty quickly at product launch).

    • Piotr

      Thank you for the update. Glad to hear they are working on it.

  21. Dan


    Does anybody know if the FR645 saves a GPX file of the course onto its memory (e.g. like a handheld GPS device does), and if it is then possible to copy this onto a computer without using Garmin software?


  22. Hathos

    Great review Ray!

    I had a FR235, but it died a few months ago out of the blue. With this, I’m convinced to get the FR645 Music, as I’m definitely on the side of listening to jams while I run. I’m just waiting for it to be available via Best Buy, due to a gift card I have ready to use with them. If they don’t end up having it anytime soon, I’ll definitely use CT and your code.

  23. Tom

    I wonder if people will be less enamored of getting Spotify on a watch now that they’ve done away with their cadence-matching Running playlists. They took that away last week, to the dismay of a lot of Spotify users.

    link to community.spotify.com

  24. Robert Scriven

    Where is the 245 :-)

  25. I’ve been using the FR630 for the last couple of years; actually 2 units as the first one failed after 9 months.

    One of the weird idiosyncrasies I’ve found with the 630 is doing track intervals where the distance is generally over-measured by 10% (after making any adjustment for which lane I was in). I know GPS isn’t always that accurate, however the reason this irks me is that of all the other watches being used at the same time (incl other models of Garmin, TomTom, Suunto) they’re all a lot closer, which suggests it’s something to do with the 630 (I’ve reset, made sure it’s 1s, GPS+Glosnas etc).

    I don’t suppose you have had any experience of this, or importantly how the 645 gets on with track running?

  26. Jeff N

    I notice the elevation data from the 645 in all of the runs you linked are about 525 meters above the other sensors and on the bike rides is about 300 meters above the head units. Does the 645 have a barometric altimeter and can you calibrate out consistent errors?

  27. Alan Sickler

    What I’m excited about is ditching the weight of my iPhone. However, it doesn’t seem like Apple Music will either a) let me store songs on the device or b) work with the device itself like iheart radio and such. Even streaming though, you still have to bring the phone. I know I COULD buy an Apple Watch, but I love my Garmin, which I think are vastly superior given that I run about 45 miles a week and bike about 60.

    Ray, non-related question – I’ve had my Fenix 3 HR for a couple of years now (love it), but am interested in upgrading to a new Fenix. Do you think they’ll update or refresh the Fenix 5 line soon, or will they more likely go Fenix 6 next year or so? I know you probably have no idea…just wondering your best educated guess.

  28. Aaron Johnson

    I’ve been wearing the 645M since last Thursday and can say I’m extremely pleased with it for the most part. I’m coming from the 630. Music works very well with my Bluetooth headphones, gps locks on quickly and maps seem very good, love not having the touch screen anymore, and the UI is very similar to past Garmin designs and I was able to figure out quickly. Built in heart rate works well 24/7, and works well on runs even. In the past I used the Scosche Rhythm+ with my 630 to record heart rate. Only problem I’ve come across is using the built in HR for strength training or cardio at the gym. For some reason, it always shows a very low heart rate. When I know my HR has to be 120-130, it displays 80 or so. No matter how I move the watch around, up or down the arm, or where it’s placed it still shows a low HR. Not the end of the world as I’ve experienced the same thing with the Apple Watch, but was expecting it to work a bit better since the running HR seemed so spot on. Guess I’ll contiue to use the Scosche at the gym. All in all it’s a great step forward for Garmin and I’m very pleased with it!! Any others experienced HR problem using the strength activity??

    • Eni

      Strenght Training moves the wrist too much, which makes OHR struggle (this is a well known “problem” for OHR, when worn on the wrist). Just for fun, I once strapped my VAHR to my ankle (it just barely fit), and the readings during a HIIT strenght workout wer actualy surprising accurate. Now I just use a chest strap. Doesn’t really bother me, I’ve been wearing them for the past 15 years while doing sport.

  29. Rich

    Hey Ray, thanks for the review. Mine arrives today to replace my FR220. Is it possible to turn the fitness tracking off? I will probably wear this most of the time just for the time, but I really don’t want to track steps/stairs/sleep or anything else, except when I’m running. thanks!

    • MattB

      Yeah you should be able to – you can on the F3, and everything newer than that is derived from the same code base.

    • Garmin-Joey

      Activity Tracking can be turned off. To do this access the Menu>Settings>Activity Tracking> Status>Off

  30. guymbr

    Hi – great review – I have the garmin forerunner 610 – Which I use mainly for running and training for 10K’s and half marathons – I am generally happy with it, apart from unreliable heart rate readings, and the need to replace the watch strap too many times. What would you recommend as the step-up up from the 610? – I will be happy to click thru from your site to make my next purchase – thanks Guy

    • Joop Verdoorn

      I was a FR610 user and the jump to the FR630 was huge. The possibilities with CIQ apps and datafields are a game changer. From the FR630 to the FR935 (which is more or less the same as the FR645 except for the triathlon functionality) was not such a big step. From FR610 to the FR645 is significant and well worth the money

  31. Greg

    I understand reserving open water swimming, power meter support, and triathlon mode for the triathlon lines; however, I can’t understand why Garmin left golfing support off the 645. It’s in the vivoactive 3. If the 645 had golf mode it would be perfect, at least for me — all do (or at least all I want to do) is run and golf.

    Any insight, Ray or Joey?

    • Garmin-Joey

      Historically Golf has not been included on Forerunner devices. The Forerunner 935 being the exception since it is the newest multisport device.

      Currently there is no plan to include Golf on the Forerunner 645

  32. James F.

    Thank you for the detailed review as always! Been looking forward to this watch greatly. But now comes the eternal question: What are the odds of a FR245 at a friendlier price point?

    Garmin’s strategy is clear in my opinion: milk the music feature at the higher price point for all it’s worth before bringing in a cheaper option. But the Vivoactive 3 seems to overlap too heavily – especially at price point – with a lower-tier FR model to the point that arguably the existence of a FR245 would either make itself or the VA3 instantly extraneous, especially if a FR245 had music storage/playback.

  33. Juri

    Just to get some clarification on the cross-transfer of advanced data:

    I have a Garmin 820 and a Fenix 5. I dont care about having all the data up to date on my 820, but will i be able to finally stop recording rides on both devices and and just use the 820. Then the data gets synced to the Fenix and i have a complete picture there. The double recordings are pretty annoying. (it reads as if it wont be possible which i find pretty frustrating as this would be just server calculations from the 820 fit file)

    • Andrew M

      One of the better suggestions to eliminate double recordings I have seen is to have your Edge and Fenix syncing to different accounts. You still need to record on both devices, but at least your data is not duplicated. Of course, it may not be worth dealing with this given better intergration is supposed to come in April.

  34. Patrick R

    Thanks for the review Ray!

    I don’t use Strava Live Segments anymore now that I know how they actually work.

    In short, your watch could tell you that you are ahead of your competitor, when you actually aren’t.

    See my comment here (link to support.strava.com)

    This seems like something you would usually call out, but I haven’t seen it discussed in your previous posts so I’m not sure you are aware :)

    • Robin

      Interesting. That means on the main segments that I track which are steep at the start, and shallow at the end, if I’m ahead on the steep part, I’m doing pretty well!

      I’m happy enough with the Live Segments as they stand but dynamic pacing would obviously be better.

    • Tim Grose

      Strava look to be answering about their own app there. If Garmin use average pace on live segments I have not noticed.

    • Patrick R

      I made a community post but Strava support turned it into a private post.

      I had specified that I was asking about behavior on Garmin devices and I got the same answer.

    • Garmin’s devices don’t match what Strava’s own app does. I actually asked Garmin’s cycling lead PM about it last summer, here’s what he had to say related to some other Edge 1030 things:

      “All of our devices are second by second comparisons and not the average. We also offer suggested segments for download with the new Segment Explore feature based on user location. The new Strava Routes Connect IQ app will be preloaded on the Edge 1030.”

      The first sentence is the most important piece.

    • Patrick R

      Nice that’s helpful but I’m still not 100% convinced, maybe Garmin-Joey can chime in :)

      If Strava is just feeding Garmin “averaged segments” then even though Garmin is comparing “second by second”, it’s still against an averaged segment.

      I’ve noticed some weird behavior during live segments, could be because GPS jumps around, but I wouldn’t be surprised if Strava only exports the total elapsed time and segment routes to Garmin (vs individual GPX tracks).

    • Patrick R

      *(vs individual and not-averaged GPX tracks).

    • Garmin-Joey

      Just to add to what Ray said above, Our Strava segment is second by second- e.g. we calculate how far ahead or behind you are vs. the VP based on the selected VP was actually going over that section of the course, not just their average for the overall segment. This is important in segments where you have ascent/descent sections.

      Variation in segment behavior can come down to GPS signal. It can either be your or the person that you are competing against.

  35. David Goodbourn

    Hi does the 645 give the option of 4 data fields on one screen when running?

  36. Daniel

    First of all thank you for the thorough review!
    Second, thank you for the CT VIP Program!
    I used your VIP link and first purchased FR 645 and got $44 in points.
    Then I used the points to buy the Garmin Pod(regular $69) for which I paid only $25.
    Now I’m really excited to try them out both.
    Thanks again!

  37. Jon

    Eliminate the chrome look around the bezel and go with the all black look. It looks sleeker and allows for watch to be worn as a casual/dress watch.

  38. Matt Small

    Any more insight on Spotify? Spotify was on Samsung watches such as the Gear Fit2. Did they sign a sole-provider deal with Samsung prohibiting them from going on other makers’ wearables?

    As an aside, the Spotify app on the Gear Fit2 was great for downloading playlists. The downside is that the watch is awful aside from anything other than basic step counting / activity tracking / phone notifications. Don’t get me wrong it looks great, but with GPS on and music playing the battery life lasted about 30 minutes into a run! (Thankfully I had my Garmin on my other wrist).

    • Garmin-Joey

      We are actively working to bring music service providers iHeartRadio and Deezer to the Forerunner 645M. When available these services will be enabled through a download from the CIQ App Store.

      We continue to explore expanding this offering by including CIQ applications from other music service providers.

    • Morten

      I guess Spotify has a very big backlog of features they want to implement for smartwatches. Garmin has only the 645M that supports music which represent a VERY small group of users compared to both Apple and Samsung. I don’t see any reason why Spotify will make an app for Garmin any time soon.

    • Note that Spotify doesn’t actually have an offline app for the Apple Watch.

  39. andrew c

    How does the backlight work on this? I have to change a data screen on my FR235 to see my watch face at night.

    • Garmin-Joey

      The Forerunner 645 has an option for Gesture in the backlight settings for both During Activity and Not During Activity. The Gesture feature allows the backlight to come on by raising your wrist. You wouldn’t need to press a button.

      You can also customize the backlight to stay on all the time for activities.

      More information can be found in this link: link to www8.garmin.com.

    • Treadmore

      Andrew – the top left button on your 235 should activate the backlight without changing data screens during a run.

  40. Robin

    Hi Ray. Just to clarify, as a runner and a cyclist, the training load metrics don’t work (or at least don’t capture the bike load), regardless of what device you have unless you have a power meter on the bike? And the new updates won’t change this?

    Thanks for all your hard work.

    • Patrick R

      I think the Training Load metrics work without a power meter (you just need a HRM). When I ride indoors on a spin bike with my 935 it still shows me an Aerobic Training Effect after the workout, and my Training Load increases, even though I don’t get power data from the spin bike.

    • To clarify, meant training status. None of my rides appeared to impact training status on the FR645. When I asked Firstbeat they said:

      “The big thing we would get from the power meter is a measure of external work load that allows us to create the necessary context for VO2max detection. Without that element we are limited to calculating the intensity of effort (0-100%) – which interestingly we measure based on modeled oxygen consumption derived from heartbeat data, not just something simple like %HRmax or Heart Rate Reserve (HRR) or something like that.

      Anyways, so no power meter during cycling = no VO2max estimate during that session.

      Not a huge deal, really, but is has the knock-on effect of not updating Training Status, which looks at changes in detected VO2max in light of your current Training Load. So, if you went for a few weeks with cycling as your only training modality, then eventually Training Status would switch to the “No Status” – because of a lack of a sufficient sample of VO2max detections.

      Training Effect and Training Load will both accumulate as normal when cycling without a power meter, so no problems there.

      The weakness are VO2max and – as a result – Training Status.

      So that’s the bad news, but not really all that different from someone who has, for example, rowing, swimming, skiing, boxing, or aerobics classes as a significant part of their regular training activities. The good news is that it really doesn’t take THAT much running to calculate your VO2max, so all it would really take is a couple 10min runs per week to keep Training Status up and running.”

    • Jeff N

      Even with a few runs per week to keep the VO2max up to date and Training Status functional, without heart rate data, swimming will not impact training load?

    • Peter G

      Hi Ray (or Garmin Joey) , on my Forerunner 935 I find that it is only wrist heart rate that adds to training load. At least my Scosche HR data does not seem to add to the training load reported on the watch?

    • Garmin-Joey

      What type of activity are you doing?

      If you reach out to Product Support you could provide some activity examples and the team would be able to look at this with you in a little more detail.

    • Peter G

      Running or trail running are my only activities. Thanks for the answer.

  41. Stephen

    I think it is time for Garmin to allow the optical HR sensor to work on the Fenix5 Series/FR935/FR635. Especially, since the Training Status needs this data to compute EPOC for swimming. As a triathlete, I now need to add more gear (Swim HRM / Tri HRM / wait for Rhythm 24) to my gear bag…ugh one more thing to charge. This does bother me since Training Peaks will give an approximation of TSS for swimming and the Garmin/FirstBeat doesn’t, which makes it useless without all the extras.

  42. The Real Bob

    For a 100 bucks more the 935 is worth it in my opinion for battery life alone. After having 30 day watch only battery life, I could never go back!!!

    I always run with my phone anyway. So unless they put a 4g radio in it and I can receive and make calls also, I will never ditch my phone thus I have no need for music on my watch. But, I guess by reading many do.

    Personally, I think they just need to take the 935 and increase the screen by getting rid of the black inner rim with the garmin name on it. Otherwise, I would change very little about the 935.

    So, if I use the 520 will my 935 incorporate the rides done into the training status on my 935? Or do I need the 1030 and 935 to do cross platform syncing?

    • gingerneil

      100% agree. Love my 935, with the battery being one of the main huge advantages for me. I use an ipod shuffle, and very rarely run with my phone. Just wish the pebble core had seen the light of day or someone else would step up. I don’t want Bluetooth headphones, and need Google music – Spotify etc is no good for me.
      One other point – huge kudos to garmin and Joey for responding here. I work for a big multinational, and I can imagine the hoops he may have had to jump to ‘authorise’ getting involved here. 1000% a good move, and appreciated by all.

  43. Dennis Piche

    First Impressions:

    Was waiting for me when I got home last night and I spent 30 minutes to an hour setting up – including transferring 3 playlists from ITunes. I would prefer Pandora or Spotify but I digress. I am fairly technical so all of this was fairly smooth. I also setup an avatar, audio prompts, and what apps/widgets were active. Finally I paired it with my headphones and foot pod.

    Coming from a Fenix 3HR this watch is small and will take getting used to. It is extremely light on the wrist compared to the Fenix which I think I like. The band is flimsy compared to the band on the Fenix. Hopefully it is durable. It was easier to sleep with this watch on compared to the Fenix. I would say it is a bit dressier than the Fenix.

    This morning I loaded/configured the Race Screen data field. Unfortunately I only set it up on the Run app so it wasn’t available to me on my treadmill run (I will add it now).

    I did a yoga session in the morning and the watch did not bother my wrist and tracked basic info during the session.

    I completed an hour long hard treadmill run this afternoon. I was amazed by the (light) weight and fit compared to the Fenix. I could easily forget it was there. I turned my headphones on and expected them to automatically connect but they did not. I went to sensors/headphones/connect and they connected. Hopefully I don’t have to do this every time. The music app worked great and I loved the audio prompts! I picked all of my songs and put them on shuffle (earlier I tried a playlist without shuffle and that also worked). No cut out issues whatsoever (indoors on treadmill). I use Trekz Air headphones from Aftershokz and I wear the watch on my left wrist.

    Once I stopped and saved the run I was presented with a treadmill calibration prompt where it asked me what my treadmill said (compared to the watch). I wasn’t sure as I had already cleared the treadmill but I think the treadmill was .1 miles less than the watch with foot pod over a 7 mile run. I entered 6.9 and it said it was calibrated. I checked the calibration factor on my foot pod after and it didn’t change so I am thinking it was a watch calibration thing? Not sure. I was then presented with some training effect information and things synced nicely to Garmin Connect on my Android phone.

    I am interested in trying the canned text messages and I have a RD pod on order.


    1) I can choose run or walk but not hike. Is there a hike app from Garmin for this watch?

    2) What do you recommend for tracking HIIT type training classes: pushups/squats/lunges/burbees/etc…

    So far so good.



    • Kerri Muldowney

      I’ve been struggling downloading my playlists from iTunes, and help would be greatly x

    • Johannes

      “I turned my headphones on and expected them to automatically connect but they did not.”

      I think it is good that they do not auto connect when you turn on your headphones. Because most of the time I use my headphones to hear music from my phone and not from the watch, so I dont want them to auto connect and drain battery…

    • Morgan McGuire

      Also curious about HIIT tracking. I found a few apps in Connect IQ but nothing that seems like exactly what I’m looking for.

    • gingerneil

      I’d just use or create a cardio app – just name it what you like. It doesn’t make any difference to how the watch actually logs the data. For accurate HR, and from 935 experience, you’ll want an external optical or strap.
      I came from a fenix 3 – didn’t realise how heavy it was until I switched!

    • Dennis Piche

      Hi Kerri,

      Are you still having trouble?
      Do you see the 645M as connected in Garmin Express?
      Are the music files stored on your computer (can you listen to them offline)?
      Do you own the music files or are they part of a service (like Spotify or Apple Music)?

      Here is what I did (on my Mac):
      1) Make sure the watch shows as Connected in Garmin Express.
      2) Select the Music tile.
      3) Select My Music at the top.
      4) Select Playlists on the left.
      5) Select the Playlists I wanted to transfer.
      6) Hit the “Send to Device” button.



    • Kerri Muldowney

      Thanks, I’m out for a run in a bit so when I get in I’ll give it a go x

  44. Tim J

    I was hoping the FR645 optical HR sensor would be a nice upgrade over my FR235. The 235 sensor works great in general, but it’s somewhat laggy at tracking rapid changes, like intervals. I was hoping the FR645 would nail this. Sounds like I’d better wait. I’ll look forward to any updates you can provide.

  45. Kerri Muldowney

    Love my 645, been out once running in it, I’d be interested to know if amazon music will be in board for the streaming service, as I don’t use deezer and live in the UK so heart radio is out.

    • Garmin-Joey

      Garmin is actively working to bring music service providers iHeartRadio and Deezer to the Forerunner 645M. When available these services will be enabled through a download from the CIQ App Store. Garmin continues to explore expanding this offering by including CIQ applications from other music service providers.

  46. Ron

    Is it available yet? Wifey has been waiting very impatiently lol

  47. Kyle Polansky

    Interesting note about not tracking sleep during naps. I’ve found this to be consistent with my FR935. When I was working a 9-5 job with a steady sleep schedule, everything worked great. However, back in college when my bedtime can be anywhere from 9pm-4am, with up to 2-4 hour naps during the day, it has a hard time tracking.

    Funny example, this past weekend I was “sleeping” though a 30 minute walk, 5,000 steps, and about 2 hours of volunteering at a marathon. My HR was around 90-100bpm (sleeping HR is around 40), and MoveIQ even detected my sleepwalk.

    That being said, it does track pretty well when I go to sleep and wake up within an hour or so of my pre-defined sleep hours.

  48. Jani

    on a mac, the only way to add music without Garmin Express and iTunes was Android File transfer tool.
    As on Windows, device appears as 2 separate partitions

  49. Andy Banks

    Ray, great write up as ever. I’m considering the 645 as a pressie for the wife’s birthday so is insightful as always.

    You talk about the cross transfer of first beat training data coming in April. This is really needed for anyone who uses more than one device; my edge 1030 constantly says I am under training while my Descent has me lower level of optimal.

    That said the descent is missing from your list. Is this a blip, or are Garmin genuinely not planking to support it?

    In fact I’m surprised that the descent has not had any firmware updates at all yet. In theory it’s a more expensive and newer F5x, but guessing the safety aspect of a dive computer is limiting the cadence here?

    Thanks in advance.

    • I’ll confirm, but would assume it’s part of Fenix 5.

      I did confirm that Chronos is not on the list.

    • Andy Banks

      Thanks Ray,
      fingers crossed as it would be an odd miss since it has the same training load as the rest.

      The whole scene around the Descent is really quite; they seem to be so thin on the ground, even Garmin don’t seem to remember them / believe they exist :)

  50. Alexander Hall

    My 645M has arrived and so far is working well. Was a big upgrade from my previous VivoActive HR. Have connected Beats X headphones to the watch with no issues. I wear the watch on my left hand and have had no drop outs or audio issues.

    I am having errors connecting to WiFi which I’m still trying to debug to find out if it is my network or the watch.

    Overall, very pleased so far.


  51. JMi

    Is it possible to listen to music while swimming?
    In other words does Bluetooth work underwater?

    • Kyle Polansky

      While I haven’t tested this, it seems as a Bluetooth signal would only work for a couple of inches underwater, as it’s a high frequency 2.4GHz signal. Considering that Ray had issues while running through air, and water is much thicker, I would say bluetooth music while swimming isn’t possible. Perhaps possibly in openwater mode using the swimcap method since it’s a few inches from your ears, but since this watch doesn’t have an openwater mode, that wouldn’t work either.

    • Kyle is correct, the signal only goes about 1-2 inches underwater.

  52. Martijn Smale


    I now know what to do :-)

  53. Karen

    Are you able to listen to podcasts on the 645M?

  54. Steve

    Hi Ray or Garmin Joey,
    Since the watch doesn’t seem to support open water swims could it be used in run or walk mode whilst swimming in open water? And then change the workout type after in either garmin or strava.. Thanks much, great review, great watch except for open water swimming..

    • Garmin-Joey

      Devices that have open water swimming include a feature that allows for the watch to handle the GPS interruption when going into the water better than devices that do not include this feature. If wearing the Forerunner 645 on your wrist while swimming you likely won’t get great GPS data if using a Run or Walk profile.

      If you leave the watch in a swim cap, so there is no GPS interruption, it should work.

  55. Kyle

    I work with blind and visually impaired athletes and when I saw Garmin announce this watch I got excited for the potential use those athletes could put it to. Does this watch have any ability to pair headphones and instead of playing music, read distance or pace out loud? Thanks!

    • Garmin-Joey

      The Forerunner 645 Music has Audio Prompts directly on the watch and go to Bluetooth headphones. The following Owner’s Manual link has more information about using and setting up this feature: link to www8.garmin.com

    • Lisa

      Hi Ray/Joey. Looking at the manual, I couldn’t tell if the audio prompts are also available on the non-music 645. Are they? Many thanks

    • Lisa

      Oops. Found it, and the answer is yes, if using a connected phone running Garmin Connect. Thanks again.

  56. Jimmy

    Hey Ray,
    Thanks for the super-thorough review! Just out of curiosity, did you do any weight training with the 645? Was the rep counter fairly accurate, or did you find that it was having trouble keeping an accurate count for you?

  57. Morgan McGuire

    I received my 645m yesterday and wore it for a run this morning. I LOVE it. The biggest selling point for me is the size. I have tiny wrists and every fitness watch is huge on me and looks ridiculous in my professional office setting. This one doesn’t. It’s big enough to see the watch face at a glance, but not so big that I feel self conscious about it in public. So I just wanted to share that for anyone who has the same problems :)

    It didn’t track my sleep last night and I’m not sure why – hopefully it does tonight. I will see how it goes tomorrow morning in the gym for an elliptical and HIIT session.

    I’m looking forward to learning all of the awesome things it can do, but already I’m super impressed with it and happy with the purchase. Ray, thanks for the thorough reviews and help, as always!

  58. coach Dion

    Good Morning

    Just looking at your pictures and seeing that the time (while on stand-by, used as a watch) is over 2 lines… I hope one can change that because I hate hate hate that!!!

    But my 910 still works!

  59. T-Doc

    Hi DC
    Great review as always!
    It would be nice to get some details on how the WiFi workout sync works. Is it as reliable as the one in Fenix models? After your review, I’m considering this as a good upgrade from my old Fenix 3.

  60. Stefanie

    Awesome review, great work!

    I got my 645M last week. I’ve noticed that it reports my resting heart rate as very low. In fact it never correlates even close to the lowest point on the graph above. I used to wear a Fitbit HR and the RHR reported on that on average was 10-20bpm higher than the 645 is reporting. Apparently I’m suddenly insanely fit which is definitely not the case. I guess the Fitbit was probably being conservative but I don’t understand how Garmin calculated it.

    If it doesn’t even correspond to the lowest point on the graph is this just wrong or an oddity? I feel like it’s faulty as it’s so much lower than expected and I can’t even find a reported reading so low each day. It can be reported as up to 10bpm lower than the lowest graph point! Am I misunderstanding how this works? Thanks!

    • Fitbit has always been wonky high.

      The whole graph thing is what I noticed as well (see my comments up above on it). Though, it almost sounds like you’re seeing the inverse of me. Perhaps we can trade?

    • Erica

      This is something I’ve noticed too on this watch. Resting heart rate for last day is showing 33. I wish I am that fit. My usual is 47-49. Not sure what’s going on, and as you mentioned, it doesn’t even show up as a lowest point in the heart rate graph. So confused.

  61. Sean W

    I’m a very occasional swimmer. I like the smaller size of the 645 vs the 935 but will the 645 be able to include my swims in it’s calculation of my Training Load and Training Status? Seems a bit of a gap if it can’t. Thanks and great review, BTW.

  62. Darren

    I’d also like to know about this. Especially since the weight of the music is larger than the non-music, so clearly some things are different between the two watches.

  63. Gavin

    Comment so that I get updates on the comments

  64. Wouter

    Thanks for the nice review as always.

    As we need a bluetooth headphone anyway, I wonder: why is there no company making a good/light bluetooth sports headphone which has memory and functionality to sync music with your phone and/or Spotify?

    I currently have a FR 935 of which I am mostly happy. Having music without a phone would be great. However, I don’t consider any watch which is not easy to wirelessly sync music music or podcasts with phone, ideally using Spotify.

    A bluetooth headphone with memory and sync capabilities should be cheaper than buying a new watch (over and over again) and better from charging point of view -> you need to charge headphone and watch independently anyway?

    The closest thing I know about is the Sony B-trainer (I wonder your vision on that as well ;-) ), but I wouldn’t need its GPS or other sensors, and it is too expensive or heavy.

    Are you or anyone aware about a good alternative?

    PS: I currently use the Plantronics Backbit fit headphone, which is great, adding bluetooth music to this would make it a killer …

    • Jeff T.

      I had an older version of the same Sony headphones but it only has mp3 capabilities, they do fit great and worked like a standard mp3 player to upload music although it does look hideous large.

      How about the Samsung Gear IconX, it’s got built in storage and is true wireless with a very small form factor. Not sure if it allows to wireless stream or upload music from it using Google music or Spotify.

    • Kevin L

      The Samsung Gear Icon X have 4GB of built in memory for holding music:
      link to samsung.com
      link to theverge.com

      I suspect that you cannot sync with Spotify however.

    • Wouter

      The Samsung Gear IconX looks interesting (but expensive), indeed a lot smaller than the Sony. Thanks!

      … the smallest setup with offline Spotify then still seems to be the Mighty (someone should integrate this thing in their headphones!).

    • gingerneil

      The mighty is promising – but the battery life is a showstopper for me.

    • Sherry

      I have the Mighty and my only issue is the connection to my earbuds. If its not clipped to my shirt next to the earbud it ‘s connection is wonky.

  65. Joe

    Out of interest has anyone had any issues with STRYD I did my first run yesterday and it all seemed spot on, but today, it dropped out, and the pace on a couple of my miles was a long way off. I have previously used a stryd with 230 with no drop out issues. I have the 645music, and the Bluetooth here has been fantastic. I wear the watch on the opposite wrist to the stryd, so maybe it could be to do with that. I use the stryd as both pace and distance measurements, used gps yesterday, and glonass today… any advice?

  66. Olly

    Hi Ray,
    this is the most interesting part for me:
    “Garmin says they’re working on it, and in fact just yesterday committed that this feature will roll out starting in April to devices that support these new metrics. It’s already being used/tested internally at Garmin. Specifically, the following units will cross-transfer the advanced data:

    Edge 1030
    Fenix 5/5S/5X
    Forerunner 645/645 Music
    Forerunner 935
    Vívoactive 3”

    Well, can you share more about it? Have you tested it already, does it work?
    I’d like to get rid of my FR935 during bike rides ;-)


    • Yup, I thought folks would enjoy that nugget.

      Nothing more to share at this time, I haven’t tested it yet. Sounds like the dates/timeframes are pretty well set though.

  67. Devon Q

    What is the glass display made of? I have a Fenix 3 Sapphire and it’s saved me a few times. Thanks.

    • Thomas B.

      Good question… we’ve heard about sapphire glass, gorilla glass, etc. Where does the FR 645’s “chemically strengthened glass” fit in on this spectrum of glass durability?

    • Devon Q

      Scratch-resistance > shatter-resistance … it’s on me if I drop or slam my watch on something.

    • RTellis

      “Chemically strengthened” glass is Gorilla glass. In the early spec sheets on the Garmin site after the announcement at CES that’s how it was listed. I don’t know why they changed it.

    • T

      Have anyone thought about putting liquid nano for screen protection? Or using any screen protection?

  68. Andy Banks

    Ray / GarminJoey,
    Is the Descent MK1 a deliberate miss from this list?
    Would love to have the first beat training stuff working across my edge 1030 and Descent.

  69. Greg

    VERY disappointed in the connection with Apple AirPods thus far. What are the odds this can be fixed? Anybody have any info on this?

    • Garmin-Joey

      We are aware of potential issues when using Forerunner 645 Music with AirPods outdoors. The following FAQ link has more information and some suggestions:

      link to support.garmin.com

    • Jeff T.

      Same experience here with my Airpods using Outdoors. It doesn’t just cutoff a little. It cuts off continuously and stops completely, I have to select play again and again.
      So looks like this is a know issue as per Garmin Joey. Unless this issue can be resolved I see a potential for many returns.

    • Mike

      That FAQ was not helpful whatsoever

    • Jeremiah

      If I can’t use my AirPods reliably with this watch, I’ll never buy it. That is super disappointing.

    • Brian Simpson

      Yeah the Garmin FAQ is basically a non-apology for not supporting any truly wireless bluetooth headphones/earphones. If you look at the official list of supported/recommended headphones/earphones you will probably notice that the only models on the list are all corded models, i.e. those earpieces that are connected to each other by a cord. And no mention of other non-Apple truly wireless models such as the Jabra Elite Sport or Bragi Dash products. Why is that? Probably because they have poor connection problems to the 645m as well.

      Let’s face it – Garmin is buying off the shelf bluetooth chips and associated firmware and dropping it into their watch. Antennae placement can only happen within the watch in a very few ways so that probably has no affect on connection issues. Basically the fact is that Bluetooth as a whole sucks and if you are not willing/able to make modifications to the hardware and firmware (Apple and their W1 chip and “special sauce”) then you get what you get which is mediocre at best. If you find something that works fantastic, if not, then that’s a shame. For all of us.

    • Matt Treavis

      I can’t comment on AirPods, but am happily using Jabra Elite Sport truly wireless headphones with my forerunner 645 on my right wrist (note the right earbud is the one that links to the audio player..)
      The only quirk to report is a slight delay (sub 1s) to audio prompts to the left earbud. This doesn’t affect music, so I’m not that bothered.
      Overall very happy with this setup.

  70. KHarp

    Still waiting on mine. Ordered it on January 29 from Amazon. Anybody already received theirs after ordering on Amazon?

    • Xcmets

      Also waiting on Amazon. Ordered on January 8th with one day shipping. It hasn’t shipped according to Amazon but is slated to get to my house by 8pm, just 9 hours from now.

    • Xcmets

      Update: Delay has pushed delivery estimate back to Friday. Grrrr

    • Sherry

      I ordered a black 645m from Amazon on March 1st and I received it march 5th. Mine came from Heartrate Monitors USA. Looks like now they are out of stock again.

  71. Marco

    Hi Ray!

    My 630 has been acting up since 2 months ago (not syncing over bluetooth, wrong clock time, etc) so I’m now looking for a new one… I’m going to buy the one you say is better for me: I just run and weight lift. I’m liking the 645, 935 and the Polar M430. Most important feature for me would be HR accuracy. I hope you can help me out!

  72. Morgan McGuire

    Did you order a 645 or 645m? Looks like they had 645m in stock for a while but no 645’s. I ordered a 645 from amazon and am supposed to have it by March 23.

  73. Sebastian Greensmith

    Would you expect these to grow from there? What about in the UK…iHeart Radio isn’t over here so would it just be Deezer. Also any word on how streaming would actually work with the Deezer subscription considering there is no data on the 645M so how will it stream music…would it need your phone to stream music?

    • Garmin-Joey

      When the Deezer app is released it will function very similarly to how iHeartRadio will function. You create your playlists on Deezer and when complete it will sync the music through Wifi to the Forerunner 645 Music. This will allow you to get the music from the streaming service on to the watch and run without the phone.

      We’re actively working to bring music service providers iHeartRadio and Deezer to the Forerunner 645M. When available these services will be enabled through a download from the CIQ App Store. Garmin continues to explore expanding this offering by including CIQ applications from other music service providers.

    • Mike St Louis

      I’m confused by this as well.

      Does streaming *only* work when you are connected to a wifi network? That doesn’t seem reliable.

    • Garmin-Joey

      Wifi is used to download the music from the service to the watch. When the download is complete the music files are locally on the watch so that you can listen to the playlists without needing to be connected to the phone.

    • Mike St Louis

      I see. Thanks for the clarification. I was looking hard at the 935 but this music functionality is very compelling.

  74. Sebastian Greensmith

    So it’s not actually streaming at all. Simply transferring from a streaming service. You won’t be able to then select another song whilst on the run that you haven’t previously transferred.

    I’ll repeat my first question…are there any other plans to introduce anything outside of Deezer in the UK? I know you’re working hard to bring Deezer to the weather but can is it possible to just give a yes or a no rather than the boiler plate answer that has appeared multiple times above?

    Also Garmin Pay in the UK. Danske Bank the only supported bank which isn’t even a mainstream bank in the UK? Surely you can do better than that. Confused at the rush to get the watch out given the two flagship features aren’t properly working yet.

    I bought the 645M but considering returning for the regular one at the moment.

    • Dennis Piche

      Streaming services offer offline content – which is different than static offline files that you purchased/downloaded. This content can be in the form of a dynamic playlist which will be updated every time your watch connects to WIFI. So its somewhere in the middle.

      Of course I would love to have Pandora or Spotify but might be willing to give Deezer a shot for a few months. Not sure I am interested in IHeartRadio.

      Basic transfer of my personal static playlists works great. Trying to figure out how to get an audio book onto my computer then onto my watch.

  75. Kieran B

    Hi Garmin-Joey,

    Will Garmin Pay work with any Irish banks anytime soon? If you can get AIB Bank or Bank of Ireland on-board with it, it would be great.

  76. Yvan

    Anyone got connection losses of connections with ANT+ sensors like reported on the Fenix 5?
    I want to buy the 645 instead Fenix 5S because of that problem.

    • Tessa

      I’ve only tested with 2 different ant+ usb sticks (one from Garmin & one from Suunto) + Trainer Road on my comp, but I’ve had zero connection drops over multiple days of use for 4+ hours at a time. I haven’t tested with any other sensors, but I’d be super surprised if it wasn’t just as solid at this point. Before this watch launched, I’d had constant connection drops with both the Vivoactive 3 & Fenix 5 as I attempted to upgrade from my 735xt. I was fully prepared to return this watch too if similar issues showed up, but it’s been night and day to those.

  77. Alexander Hall

    I’ve posted the following about WiFi connectivity issues in the Garmin forum but thought I would also ask here to see if:
    a) anyone else having a similar issue
    b) any suggestions on how to resolve

    Watch: Garmin FR645M firmware 2.40
    Routers: 3xNetgear R7000 running DD-WRT v3.0-r33675M kongac
    SSID: Routers share same SSID but broadcast on different channels. Have also tried with just one router using an SSID.

    1. Testing Network Connection via Garmin iOS: Connection Successful
    2. Adding a new Network via Garmin iOS: Successful
    3. Adding a new Network via Watch: Successful
    4. Manually connect to a Network that is already set up using “Connect to Wi-Fi” in watch settings: FAIL.. Sits on “Searching for Wi-Fi network” for ~2 minutes before displaying “Network error. Try again later”. This happens 100% of the time from what I can tell.

    I’m not sure how the watch is meant to handle WiFi vs Bluetooth. Can the watch only connect to one or other, does one have priority over the other, etc? Does anyone know?

    Any thoughts/suggestions?

  78. Victoria

    Hey Ray or Garmin Joey,
    I was using the forerunner 220. When doing intervals, there was 5 beeps counting you into the interval. Letting you know it is about to start. And 5 beeps letting you know the interval is almost over. Do you know if the forerunner 645 can do that as well? I have looked through all the menus but can’t find that particular setting.

    I do love using the forerunner 645. I have not had any issues with headphone connectivity or them cutting out. I am using the JBL Reflect Contour. Music was easy enough to load from my iTunes music. If anyone is hesitating buying this watch, don’t. It looks amazing. The screen is really clear and crisp. Really looking forward to getting the physiological features after building up my run history!
    Thanks in advance guys.

    • Garmin-Joey

      The Forerunner 645 does have the option to give an audible tone that will count down before the start of the next step in the workout.

      You will want to make sure that Alert Tones are enabled “During Activity”. Access the Menu>Settings>System>Sounds>Alert Tones to check this setting.

    • Victoria

      I did have the setting that way during my activity. I will turn it off and then back to during activity and see if that makes a diffence. I’ll see if that works next time. Thanks Joey.

    • Garmin-Joey

      Hi Victoria,

      There appears to be an issue on some devices where, even though the setting is correct, the alert tone isn’t working. A workaround is to turn Alert Tones on and then do a mock interval activity. You can then set Alert Tones to ‘During Activity’ and they should work as expected moving forward.

      We are actively investigating this.

    • Victoria

      Thanks Garmin Joey, that completely fixed the issue.

  79. Morgan McGuire

    I did intervals with my 645 today and I didn’t hear any beeps (though it’s possible it did beep and I didn’t hear it). I was hoping it would be similar to intervals on my Fitbit Charge, it vibrated at the start and end of every interval/rest period. Today I had to keep looking at my watch to see how much time was left. I will investigate more to see if I can figure anything out because intervals are a big part of my workout. I feel like there’s so much I still have to learn about what the watch can do!

    • Victoria

      I did intervals too. It did vibrate and then a voice came on telling me the interval was done and said the time it took me to complete the interval. I like the count down so I know it is almost over LOL! And sometimes I speed up just a little.
      And I agree, I have a lot to learn too. In one of the questions above, Garmin Joey linked the PDF manual to the watch. I have been looking at that to get more familiar with the watch.

    • Morgan McGuire

      Oh, good to know that you had vibrations! Maybe I’d turned off alerts or something. I was also listening to music through my phone and headphones (not through the 645). I created my own interval workout (45 sec work, 15 sec rest, repeated 30x) in the activities section but there are probably other ways of doing it. You’re right, the PDF manual that Joey linked has been super helpful!

  80. Gabe

    Nobody wants those music services lol

    Spotify is king baby!

    • Tessa

      It hasn’t been expressly stated anywhere regarding Spotify, but from reading many of Ray’s recent reviews and other things on the internet (take this with a grain of salt, I’m not an industry expert) it REALLY sounds like most of the streaming services have some sort of exclusivity contracts in place with specific watch manufacturers. Pandora for Fitbit, Spotify I think with Samsung gear? iHeartRadio and Deezer are just sources Garmin was able to actually work with at this time. The platform on the 645 is very wisely built in such a way it COULD work with other providers like Spotify in the future, but Spotify would have to agree to that, it’s not up to Garmin right now. Making sure the watch could be compatible in the future once certain music providers aren’t exclusive anymore is the best they can do.

      Fwiw, I find it totally absurd from a consumer view point that music providers are doing this, especially since many of us pay for Spotify premium for instance already AND they have the Mighty as another mobile streaming-storage platform, so maybe they have more wiggle room in terms of exclusivity than they are letting on. Imo, It SHOULD work the same way as it does currently with different phone manufacturers, where everyone just has apps that work with a variety of devices. But I’m sure they’re all being paid well for their exclusivity so who knows from a business standpoint when or if they will decide to/can let that go.

      One thing that hasn’t been talked about anywhere that I’ve been able to find is if there is any chance of an Audible or Amazon Kindle app for CIQ that would allow the playback and maybe even sync of audiobooks. Audible has SUCH control over the audiobook industry & it’s fantastic to be able to be reading a book on my kindle app on my phone, get on my bike, turn on Audible narration, listen while I ride right from the spot I left off reading, get done with the ride and have the text version be synced to exactly where I left off listening on multiple devices! It’s a gem of a system and I would LOVE if it was brought to the 645 via CIQ in some way.

    • Kerri Muldowney

      What a great idea about audible, would be great as I use it for running.

      I at the moment use amazon music so waiting to see if amazon come on both too, exciting times 😁

    • Joe

      Regarding audible – I have only ever used it on my iPhone… Is it possible to download books from the audible website to the hard drive of a PC and then transfer them onto the 645 this way?

    • Dennis Piche

      Following. I have some audio books I purchased from Google play books. They are downloaded to my phone but I can’t figure out how to download to my computer.

    • gingerneil

      I would love to see a small screenless android device – that, I assume, would be able to manage things like spotify and google play music the same as any other phone, and without needing further royalty agreements.
      Thats what the pebble core was meant to do… but…. well…. nevermind.

    • Warren clarida

      I talked with audible’s customer service and they said that the forerunner 645 is not currently supported. Their AudibleManager software which allows transfer of audiobooks to various devices (mp3 players, cars etc) does have a “Garmin GPS Device” plugin so there may be some hope that they support it in the future.

    • Dennis Piche

      RE Audible: I chat’d with them today on this subject. While their support page says garmin and tomtom gps devices are supported only nuvi devices are supported on the garmin front.

      They said the manufacturer needs to be involved and needs to allow them to update the firmware on the device (to transfer/support audible content).

      Audible has a promotion going that allows you to get the first year for $99 and it includes 12 free audiobooks upfront in addition to 1 per month. It also includes a $50 rebate for an Echo. I would love to buy in but only if I could use it on my watch.

      Has anybody tested this?

      @Garmin-Joey: Does the 645M support Audible audio books?



  81. Gabe

    Hi Ray – always thorough and beautifully done.

    Any plans to start releasing video reviews in conjunction with your written reviews?

  82. JensDoe

    @anybody with UK version: what type of power plug(s) is/are included? In Germany I’d need a type C plug. Sometimes you have to assemble the charger and can connect the appropriate plug type (type G, type C).

    • Sebastian Greensmith

      No plus. Just the cable so you wouldd plug the USB end into your regular phone charger plug or direct into the wall if you have those fancy sockets.

    • JensDoe

      Thank you, nice to know.

      @Ray: thanks for this excellent review. :-)

  83. Frenchies


    Is the body of the FR645 glued together, like the FR235, or is it screwed together, like the Fenix series? I’m thinking of repair, battery change etc. This is a game changer for me as I am not prepared to invest 400+ bucks in a disposable device.
    Thanks for the feedback. Mike

    • Tim Grose

      Glue it seems. If you ever need your device “repairing” you typically send back to Garmin and they send you out a replacement. Never heard of anybody using a Forerunner for so long that the battery gave up. Of course if you did unscrew it yourself then could you be sure it would become disposable if you were unable to get everything back in properly…

    • André

      Even though there are screws on the Fenix 5 the battery is non-replaceable. See below:

      link to youtube.com

    • okrunner

      Guess I don’t understand your concern. The one that started it all, Forerunner 305 did not have a user replaceable battery. None of them have. If that is your criteria, it is misplaced. As commented, I don’t anyone who has used one long enough that the battery doesn’t charge at all. I have a ten year old 305 that still charges. It will last long enough for you to get your $400 out of it.

  84. André

    According to the specification, the class of the 645 is Corning® Gorilla® Glass 3. Is that different from the 935. Reading user reviews for the 935 I can see that it appears to be easily scratched.

    • Tim Grose

      Not sure exactly but have got both on right now and feel similar. Have used a 935 for a good year now and don’t see any scratches.

  85. Sam B

    Hi. I just wanted to point out one small feature on the 935 which I believe is missing on the 645 due to it being considered advanced navigation. It’s MOB (man overboard location). It’s very useful for those who need to constantly find where their car is parked. With the 935 you just press a hot key which will save the location and then navigate back to the car when you need to. Every time you park your car, you just press the hot key and it overrides the last MOB location, which should be very useful for finding your car.

    • Tim Grose

      You can setup a control (the ones you get to if you briefly hold down the power button) for Save Location which will achieve this purpose.

    • Sam B

      Thanks! That’s true, but I would have to set a new location and then delete it with every parking, so if you live in Brooklyn NY without a driveway, and you need to do this constantly, it should be more useful using “mob” with a hot key, where it will get saved with one button press (as last MOB), and each parking will automaticlly delete the previous one.

  86. Sam B

    Hi. I noticed in the manual of the 645 on the alarm setting that you can set predefined labels for each alarm. What are these labels? Are they written descriptions you would like the watch to show when the alarm goes off? How do you input these labels in the watch, or do you just choose from descriptions Garmin put into the watch? I understand the 935 also has these labels as they were added in a later update. I just would like to know what they are. Also, if anybody has access to both the 645 and 935 side by side, and can compare the vibration strength between the two of them, I would greatly appreciate it. Thanks!

    • Tessa

      There is a “Find my Car” CIQ app that looks like it’s compatible. The 645 does have breadcrumb navigation and back to start functionality so I’d imagine it works with that. Downloading it onto my watch now, won’t be able to test till late tonight but will update when I can :)

      Re-Alarms: it’s a single-word label with preset options like “Reminder” or “Appointment” and others. It would be great if there was a way to add a custom message there via the app, but I see no option to do so currently, maybe something for the future? Even as is, its very useful :D

    • Sam B

      Thank you so much! I’m interested to know if the find my car app works well, because the reviews on that app aren’t the best.

  87. Tonny Joost

    I´m so pleased with the FR 645 Music – from the size of the watch, 5 buttons, all the nice activites and multiple settings and the ability to play my music on the go…..
    Tried so many music/sport watches Samsung Gear s3, Gear Sport, Amazfit Pace 1 and 2, Fitbit Ioniq.

    Thx Garmin – you have a winner…..

  88. Dennis Piche

    What activity are folks using for Hiking with the 645M understanding of course that it doesn’t have maps/etc… like Fenix. Use the Walk activity?

    • Karen

      There are some pretty good CIQ-APPS apps for hiking which I used on the Vivoactive HR. DW Maps allows you to follow GPX trails, the premium version (for a small annual fee) even has alerts. For hiking without predefined trails I like Hike2.

  89. Tony

    Thanks for the great review!

    Could you comment on the accuracy of real-time pace displayed while running? I’ve been using a borrowed 235 for a month, and the pace lags so badly compared to my old foot pod-only watch that I don’t even look at that field.

    I’m tempted to add a foot pod, but my understanding is that this would override the GPS distance, and I’d lose the maps in garmin connect. Is there any way to get footpod pace while running, but use GPS for everything else? (Other than wearing two watches!)

    • Tim Grose

      Yes. If you use a foot pod in the regular outdoor Run mode you will always get the map. With a foot pod on a 645 you can optionally decide to use it for distance and/or speed instead of from GPS. Personally I only normally use a foot pod for distance and speed on a treadmill as I find the GPS works plenty well enough for me. If however you do a lot of running say in forests or city centres or on oval running tracks when GPS may not be optimum then you might want to experiment.

    • Tony

      Great, thanks for the info Tim!

  90. Ian

    Slightly OT. As Garmin are now doing watches that accept both ANT and BLE sensors, and their rationale for dual ANT/BLE Vectors was Zwift, will they be producing a dual ANT/BLE HRM and/or footpod to interface with Zwift and other online platforms?

  91. Ben Sklar

    Great review, thanks for posting! One question – did you have a chance to fully rundown the battery with GPS and music on? I’m curious if the 5 hour battery life estimate from Garmin is accurate, or if (hopefully) it’s conservative. For ultras/long day hikes, 5 hours could be limiting, even if only listening to music for part of the time.

  92. Tomas

    I am thinking to buy 645.
    What is difference when you use HRM strap and Running pod for running. Strap has better statistics?

    • André

      #216: You can read about the RD Pod here:

      link to dcrainmaker.com

      I want accurate heart-rate monitoring and therefore will continue to use a HRM strap with Running Dynamics in it.

      If the build-in heard rate monitor in the watch is good enough for you and you want the running dynamics stats then the RD Pod seems like a good choice.

    • Morgan McGuire

      André, which HRM strap with Running Dynamics do you use? Now that I have the 645 am thinking of relying on that instead of wrist-based.

    • André

      I don’t actually own a 645 (yet), but I will probably get one and in that case keep using a HRM chest strap. I have the heart rate monitor that came with my 620, but I am using the polar chest strap, since the older Garmin chest straps have known issues with dropouts (fixed in newer generations).

      I have the heart rate module in the first link below, but both of these are compatible with 645:

      link to buy.garmin.com
      link to buy.garmin.com

    • Tim Grose

      Actually you would need the HRM-Run or HRM-Tri to get running dynamics (and so be able to use running power). The “Soft Strap Premium” one will work with the 645 in giving you HR but that’s it.

  93. Morgan McGuire

    Ray, and those of you who have experience with this stat – how accurate do you feel the recovery suggestion is? And what exactly is that based on? Heart rate, plus some combination of analysis of the activities you’ve done recently? I did a pretty easy 4 mile run this morning and my 645 told me I should have 3 days of rest or easy training. I think that’s definitely erring on the side of caution but am curious what others have experienced, and how much you rely on that to guide your training. I was planning to take it with a grain of salt and keep on with my regularly scheduled programming, but maybe this watch is way smarter than I am and I should listen to it more? Thanks in advance for y’alls help and input!

    • Garmin-Joey

      There is a bit of a learning curve when it comes to the Recovery Time. Having an established Vo2 Max and Max heart rate help this information to be come more accurate over time. There is some helpful information about this, and other Physiological Measurements/Running Dynamics in the following link:

      link to garmin.com

    • Tim Grose

      In my experience it always gives rather long recovery times initially until it “learns” you. I run most days of the week and it is not that usual for it to show me much more than 24 hours. That said I did a very hard run “tempo” run last night and it is still showing 12 hours to go. I wasn’t planning on running today as am feeling rather tired from it so that makes some sense for me. If I did run it would certainly just be an easy recovery one.

  94. Michael

    Great review! I have been holding out for a Garmin watch – I am a runner, and do not swim. I don’t care for the music part (streaming is where its at!) so I want to go with the Garmin 645 non music ($399.99). So, all things being equal, is the 645 the best true running watch I can buy at the moment? Or should i go for the 935, even though I wouldn’t use it for other sports like golf etc? Thanks!

    • Ben

      The 935 would give you longer battery life. The 935 is an awesome watch. But the 645 has standard (and cheaper) 20mm quick-release watch straps and I think the 645 looks nicer. If you are OK with the battery life on the 645 I’d go for it.

    • André

      I’m also thinking about buying either of these and agree with Ben’s points. I can add that 645 is also lighter and smaller (a good thing for me, having thin arms), but from the pictures it looks like it has smaller screen bezels compared to the 935 (so smaller waste of watch space).

    • Jeff N

      I am also debating between the two. I don’t need the extra GPS battery life of the 935 but I do swim a couple days a week. I don’t know what I would do with the HR data from the swim, but I think it might be good to have it included in training load and training status. I do prefer the aesthetics of the 645. I’m torn.

    • Andrew M

      Actual display size at 30mm/1.2 inch is the same on both watches.

    • Joop Verdoorn

      The FR935 is the best running watch, in my opinion, as it supports powermeters also for running power. You can connect the Stryd footpod as a powermeter using several custom datafields, without the need of installing the Stryd datafield. Those custom datafields give running power and running metrics at one page, not limited to 4 metrics (my Datarun plus datafield for example has 7 metrics in one view). For recording running power from the Stryd it is still necessary to use their datafield, but it can be in the background.
      With the FR645 you can only use the Stryd datafield and have 3 other metrics. It is less versatile.
      For Garmin running power both are on the same level

  95. JR

    I haven’t been able to get it to work with itunes. Garmin Express found most of my music, and I can load artists or albums onto the watch, but playlists don’t show up on Garmin Express, even though I have them in my itunes.

    Also, every time I open Garmin connect, it’s about a 15 minute wait while it looks for my music files.

    • JR

      Update: From what I can see, itunes playlists are stored as edits to your library file rather than as separate playlist files, which suggests that there is no way to upload playlists, at least with the current version of itunes. I don’t know if older versions operate differently.

    • JR

      One more update, and sorry for the repeat posts. I figured out that you just need to go to the itunes playlist, then file->library->export playlist. Then save as file type 3mu and save the file to a folder that you’ve selected as a music location in Garmin Express. That partly solves the problem because now you can at least select the playlist in Garmin Express and tell it to transfer to the device. The problem, however, is that I’m just getting an error message saying that each and every one of those music files couldn’t be transferred. So I’m stuck with just listening to complete albums for now.

    • Dennis Piche

      Im using a MAC so your mileage may vary. I did not have to do anything special to access my playlists. In Garmin Express I select the Music Tile, then select Playlists on the left and all of my ITunes playlists are available to select.

    • Ned Bowen

      I had this same problem transferring playlists on my PC with iTunes.

      I fixed it by adjusting the .m3u files that iTunes exports by removing all of the extra stuff in the file and just leaving the relative filenames.

      i.e. use notepad to edit my .m3u playlist file in my iTunes directory like this ..
      #EXTINF:1373,#677: The Experiment Experiment – NPR
      d:\myusername\Music\iTunes\iTunes Media\Podcasts\Planet Money\#677_ The Experiment Experiment.mp3
      #EXTINF:4827,Cortex 65: Goals Are Dumb – CGP Grey and Myke Hurley
      d:\myusename\Music\iTunes\iTunes Media\Podcasts\Cortex\Cortex 65_ Goals Are Dumb.mp3


      iTunes Media\Podcasts\Planet Money\#677_ The Experiment Experiment.mp3
      iTunes Media\Podcasts\Cortex\Cortex 65_ Goals Are Dumb.mp3

      Then the files transfer for me.

      (I also found that I drag and drop my iTunes playlists into Playlist Creator 3.6.2 and use that program to make the clean .m3u playlists without the notepad step.)

    • Ned Bowen

      I will also say, I think that the file and directory finding functions within Garmin Express need some work.

      I have 30,000 mp3’s, years of podcasts, and over 2 million files on my computer … it takes a long, long time (~25 min) to change the specific folders Garmin express looks in for music.

      Then if I make a change to my playlists, it takes another ~5 min or so of waiting for the program to reindex my music and show me the changes in my playlists. This process also seems to crash Garmin Express sometimes. I would like there to be less waiting and crashing for this process.

  96. Andrew

    Great review as always! Do you think in the future other streaming services seem likely or have you seen info from Garmin / in the forums pointing to particular services (Apple amazon Spotify etc)? Seems like Garmin is a few years behind if they don’t put resources to build it up those streaming features as so many people are shifting to streaming stead of purchases and downloading now. You mention Spotify has turned down other wearables, why would they do that, seems like more devices compatible would be better for them.

    • André

      Given that Spotify was launched on Samsung watches and the Mightly only quite recently, despite being highly requested for so many years I wouldn’t hold my breath for it to ever make it’s way to the Garmin 645. The music (and movie) business is really hard to work with and making deals in this business appears to take years.

    • Mike

      How could you get streaming on this watch, even if it was available?? It doesn’t have a cellular connection – and you are not going to run with Wifi…

    • André

      You can use streaming services offline, i.e. downloads the songs for offline playback.

    • Mike

      Gotcha – just doesn’t seem ideal to constantly be putting on and taking off music/podcasts etc.

    • André

      Mike, well real streaming would of course be even more convenient (but more expensive, especially if you need a separate cellular account), but the offline modes for Spotify is a whole lot more convenient than manually copying mp3’s or similar solutions. But the biggest reason for using it is simply because most people use streaming services for music playback these days and already paying for them and also have their playlists in those.

  97. Karen

    I got my FR-645M two days ago, and I love it. Everything is working out of the box, music handling is superb. Today I noticed one issue, though – the navigate app is missing. The manual says I should be able to press START – > NAVIGATE to navigate to previously saved locations, but there is no Navigate option in my app list. I can’t get it back via Garmin Express or Garmin Mobile either. And I’m pretty sure I didn’t delete it in the first place. It just was not there. Is it just me? And is there any way to get it back?

    • Tim Grose

      Unlike say the 935, I don’t think the 645 has a Navigation app per se – well can’t see it on mine. However if you select say the Run app then hold down the left centre button you can access the Navigation section which allows to do a course or navigate to a saved location.

    • RTellis

      According to the manual there should be a Navigate app.
      It’s been brought up on the forum and Joey says it’s being looked into.

    • JR

      It’s a little disconcerting that things like that are missed.

    • Jim Andrews

      I’d be very interested to hear more on this, the navigation, though basic, is a key feature. I’ve just ordered mine, if this feature is missing it’s going back & I’ll go for a 935.

    • Karen

      Actually, navigation is there, it’s just not included in the app list but can be found via the options menu of the other apps like walk, run, bike. I’m sure the missing app will be in the next update.

    • That’s a relief, thanks for the update. I would definitely consider that a deal breaker for me.

    • Jim Andrews

      Karen – thanks for the update on this, likewise it would have been a deal breaker for me.

      Ray – I meant to say previously thanks for the great review. I won’t buy any sports tech stuff now until it’s had the DCRainmaker seal of approval.

      Also, as previously noted, thanks to Garmin Joey for engaging in the discussion here, that’s a very positive step and shows a commitment to engage with users & customers.

  98. Ivan

    Hi … I wanted to know if the values of the battery life change with the use of the HRM band excluding the detection of the wrist heart rate. Thank you. Congratulations for the excellent reviews you make

    • Jim Andrews

      I was also wondering about that. Presumably battery life would improve if it’s not being used to power the LEDs in the watch.

  99. Tero H.

    Thank you Ray for the review and also for the discount at Clever Training!
    I replace my 910XT with this one, and I think I will like it.

  100. Can you elaborate on what you mean by take away “advanced navigation”? What navigation feature(s) are missing compared to say a Fenix 3 if any? I’m also a little surprised how low the non-music battery life is FR645 is 12 hours, Vs 20 hours for the Fenix 3. Is the battery that much smaller?

    • André

      1. In his review he has already described the navigation features that are included, for instance:

      “Speaking of navigation, the FR645 includes a dumbed down variant of what you see in the FR935 and Fenix 5. But specifically it doesn’t include all of the software functions such as POI’s, bearings, headings, and so on. Instead, you’ve got three basic pieces: Courses (following), Activities (re-trace a past one), or Saved Locations (Navigate to a location you’ve saved on the watch, from the watch)”

      2. The battery life for 645 is 14 hours, not 12. The 645 weighs half of what the Fenix 3 does and it’s diameter is a whole centimeter narrower, so yeah the battery is smaller.

    • So compared to the Fenix 3 then the FR645 has the same navigation or am I missing something Andre? I get the deltas to the Fenix 5X.

    • André

      I’m not familiar enough with the Fenix 3 to say for sure, but the navigation features looks similar. Look under “Outdoor Recreation Features” in the following specifications for comparison:

      link to buy.garmin.com
      link to buy.garmin.com

  101. Donna

    Has anyone had any issues yet with the sleep tracking? My 645M did not track my sleep last night but if I go in and edit it to reflect the hours I slept it does update with a sleep pattern.

    • Karen

      I have worn mine for 2 nights. It tracked my sleep the first night but not the second. I’m not sure why yet.

    • Aaron

      I have found mine doing the same thing. If I charge it in the evening after work/gym, then put on at bedtime, it does not track my sleep. If I’ve worn it all day and don’t take it off before bedtime, it records sleep no problem. Not sure what to do different?

  102. Jani Kraner

    in UltraTrac GPS mode

  103. Jani Kraner

    and satellite

  104. Miguel Ramon

    Hi Ray just read your amazing in depth review, thanks!

    I saw you put the Apple Watch series 3 in comparison table side by side with the Garmin 645. How would you compare those watches with each other? It’s obvious that the Apple Watch is the better smartwatch but how does it compare against the Garmin 645 using apps like Strava, Runkeeper or Runtastic on the AW? Does it come close or is the Garmin 645 still the better watch for running? I am still undecided between those two watches.

    • Ben

      Ray doesn’t like to review watch+app combos because apps come and go. In general, Garmin is going to be a better running watch. It’s more convenient with an always-on screen and a lot more flexible as far as data screens go. It’s also a bit simpler to use for running with simple buttons for starting and stopping rather than swiping and force-pressing the screen. If you plan on running a long time, the battery life will be superior as well. The Garmin will probably hook up with a larger assortment of sensor types, if that is relevant.

      What the apps on the Apple Watch would bring are better integration with their various services. For instance, voice coaching on Nike Run Club or cheers on Runkeeper (and maybe others) when people follow along and like your run on Facebook.

      I prefer the simpler, more focused interface of the Garmin, but others will feel differently.

    • Ray I have both an Apple watch and a Garmin (Fenix 3). There isn’t a chance the Garmin would replace the Apple watch (Apple watch has better notifications, can reply, works with SIRI, Apple pay, Apple maps and the list could go on). By the same token when it comes to sports I always ditch the Apple and go with my Garmin. Ability to navigate, cycling sensors, Garmin portal, integration with other sports portals, and again the list goes on. So sadly they are complimentary. Just depends on your focus. You can read more about the Apple watch here link to johngalea.wordpress.com

  105. As always, awesome review Ray. Well done. In regards to navigation I can see that the watch has navigate to waypoint, navigate to start and follow course. What seems to be missing although I can’t tell from the manual to be sure is trackback which allows you to follow the exact path back to your start. Can someone confirm this is missing in the forerunner 645?

  106. Kevin

    Looking at the 645. If I’m pairing it with an iPhone, I’ll be able to view texts, but I won’t be able to respond. Correct?

  107. PeterF

    Any word on whether Garmin has improved the accuracy of “stairs climbed” in the past year / on the FR645? I returned a Vivosmart3 and went back to Fitbit because after climbing 15 floors Garmin only reported 3 and Fitbit was spot-on.

    I believe it was said it was a software issue, ie the sensors were fine. So I guess it’s just a matter of programming (and priority…) to fix this.

    • Morgan McGuire

      My “stairs climbed” number is always off by a lot. During a workout the other day, I ran up and down several flights of stairs, several times, and my # was something like 2 up and 1 down. Just walking my dog and doing nothing else would give me 4 flights up, 4 flights down. It’s terribly inaccurate. My Fitbit was pretty spot on too, so it seems like it’s something Garmin should be able to do a better job of.

  108. Sam B

    Hi. Are the vibrations on the 645 accompanied with a buzzing sound which can be heard by pepole near you, or is it a silent vibration? It was mentioned that the 935 have strong vibrations which you won’t miss, but it also has an audible buzzing sound. How do the vibrations of the 645 compare? Thanks!

    • Josh

      I have found the vibrations on the 645 to be noticeable and silent as compared to my 230 which were very noticeable and very loud. I’m quite pleased.

    • Victoria

      I am able to feel the vibration a good bit when running and it is accompanied by sound.

  109. Thomas B.

    Does anyone plan to use screen protectors for this watch? Any particular brand or kind recommended?

    • Josh

      I tried one and interestingly while it fit well, once I hooked the charger onto the watch, the opposite site of the screen protector came up and never did go back down well. The screen seems like the first Garmin I’ve owned that isn’t plastic and won’t need a protector. I’m skipping putting one back on.

    • David Teague

      I purchased a screen protector for the watch, and was really disappointed that it was too small. I’m thinking that since this is such a new product, they made the screen protector based on the published specs of the watch, which say 1.2 inches. However that is just the actual screen. The entire watch face is a little bit bigger, closer to 1.38 inches. I am waiting to see some reviews of other screen protectors to make sure that they will cover the entire face.

    • LF

      I bought one from a german brand named Brotect on Amazon UK (BROTECT AirGlass Flexible Glass Protector for Garmin Forerunner 645 Screen Protector Glass Ultra Clear – Extra-Hard, Ultra-Light). I already had one of this brand in a FR 230. That one worked perfectly. This one also seems fine. It definitely covers more than the one of David in this thread. It coves all the letters around the screen a leaves just a little space like 1 mm from metal ring around the screen, which I guess you need to make sure the air below the glass escapes and that you can remove it if needed.

  110. Luc

    Elevation is 150 m off. Garmin, that is poor.

  111. Julia

    debating Garmin 645M & Apple Watch 3. Currently have a busted screen first gen Apple.

    my three sticking points/indecisiveness:
    1. Cellular is nice on Apple, and running is my time to “unplug” – but would be nice to have some way to alert someone in case of emergency considering I’m a female runner, majority solo runs and on trails. and I hate running with my phone (hence yay for Garmin with music!!).
    2. Connectivity/syncing – Have had some friends with Garmin watches say that they are a bit “glitchy” when used with iOS (I have been using Apple products since the Apple IIe in gradeschool!) and all my other devices are Apple…
    3. Would like something more rugged/less breakable (the Garmin?) since my current screen broke and it costs $200 to fix only by Apple (no off-brand screen repair places can fix it) and any screen protectors/covers/cases are bulky and awkward, not to mention when sweat gets underneath makes the touchscreen unusable.
    Cost is essentially the same when you add Apple Care, so price isn’t a deal breaker for me.
    Help! TIA

    • Mr. T

      It depends on really how much customization do you want. I have yet to find a decent apple watch running app. Most are bad and almost all only provide the basic information – time, distance, pace (some offer avg pace)

      The Applewatch GPS seems to be decent and had no issue.

      I also have had Garmin and at times had syncing problems but it was usually fixed by restarting the connect app nothing major. I don’t find it glitchy, but I also have never used Andriod so I have nothing to compare it to.

      I haven’t had a problem with either screens. The 645 is not a touch screen so there is that.

    • Ben

      As far as being glitchy, I can say that the 935 has a much more consistent connection than my 235 or 735 did. I can’t explain why. The Garmin watches can actually function well with no phone at all and i think that was the ethic that went into the old generation of watches. But as customer demands changed, Garmin did something with the more recent watches so they stay connected (maybe more frequent syncing). I can’t say the 645 will be the same, but that’s when I’ve experienced over three watches.

      However, every three or four weeks it will stop talking to my phone and I’ll have to power-cycle one or both to get them in communication again. I’m not sure whether that’s my iphone or Garmin at fault. That seems to correlate to when I leave my watch at home for a few days and wear a different watch to work. But I’m not sure.

    • Julia

      Thanks! How is the altimeter on the Apple Watch 3? Wanted that since I bought the first Apple Watch…

    • Morgan McGuire

      Julia, just to share my thoughts in case you’re still trying to decide between the two. To make it super simple: If you want a smartwatch that has some running/fitness capabilities, stick with Apple. If you want a running watch that has some smart capabilities, go with Garmin. I was trying to find the perfect running watch for a long time – I first got an Apple watch, but it wasn’t enough of a fitness/running watch for me. I looked at a lot of Garmins, and ultimately they were what I wanted but my wrists were too small and they all looked ridiculous on me. So I ended up with a Fitbit, which was a compromise – it had the basic fitness capabilities. When the 645 was announced, I was thrilled – finally a running watch that wasn’t ginormous. I’ve had it for a week now and I love it.

  112. EdC

    By specs, is the FR 645 the plastic version of the Fenix 5s, similar to how the FR 935 is the plastic version of the Fenix 5?

    • The Fenix 5s is the small version of the Fenix 5. The 645 is by Garmin’s definition a running watch so it doesn’t have multisport, open water swimming, and navigation.

  113. Michael

    How are people buying this watch already? Every site I look at has it not available for “2-5 weeks still” for the past two months.

  114. Mendes

    I have actually the 935 and i am thinking to change for the 645 because i don’t do tri at all.(a little cycling)
    The only point that make me hesitate is the battery Life.
    Could you help me?
    Thanks a lot

  115. JTH

    The biggest show stopper for me is that you can’t connect to power meters (any kind).

    Even for using Stryd a FR935 or F5 is a bit of a must as you need to rely on 3rd party data fields to show instant / average power at the same time. This requires a separate power meter connection that is missing from the FR645.

    This wouldn’t matter as much though if Garmins running power would evolve to same level as Stryd and when sharing training load becomes available between multiple devices (like Edge + FR645).

    For music the main limitation is that it doesn’t really support any of the big players for streaming / offline playlists (spotify, google play music, apple music). I guess an ideal solution would be to have LTE with call back home and music. Perhaps for the next generation of devices :)

    • JR

      I’m not sure what you mean. Stryd works on 645 just like on the 935 and F5. You use the same Connect IQ field for all of them.

    • JTH

      Stryd IQ field, besides recording your running power data, only allows showing either Instant or average power, not both. So to get the other you currently need the aforementioned workaround. You can then use any 3rd party data field that shows power meter data, but it still requires the watch to make the connection (under sensor settings).

      This is missing from the 645 as it doesn’t support power meters.

      Garmin running power doesn’t have this limitation as it has several data fields to choose from and power data is calculated on the data field itself, but it also lacks the flexibility to support any 3rd party power data fields.

      Hope this clarifies a bit. :)

  116. Dennis Piche

    First half with 645M and RD Pod. Not sure if the RD Pod had any impact but I am concerned about the GPS and Altimeter.

    My GPS had me at 13.46. I know about vectors, wide turns, etc… but this is high. The guy I was running with had it at 13.2.

    Also this race was in Washington and there is a heartbreak hill (about 200ft) around mile 6. I wanted to do some overlays of heart-rate/pace with this big hill after the race and to my dismay my elevation was a flatline – not working at all.

    I will call garmin and also try some outdoor runs without the RD Pod to see if there are any differences. Any/all suggestions are welcome.

    @DCR @GarminJoey: Any ideas?



    • It’d be worthwhile to get both your .FIT files and do an overlay of the two tracks. There’s plenty of apps/sites out there that can do it, as can the DCR Analyzer (link to dcrainmaker.com).

      That’ll tell you whether his unit cut corners, or yours strayed. In general, it’s virtually impossible in any half-marathon to get a GPS track to give you 13.2mi…unless either the course was short or measured wrong, or the unit shorted it. Just based on looking at lots of tracks/etc… It requires one to run an absolutely perfect route/tangents/corners at every possible turn (details here, though it sounds like you’re roughly aware of this: link to dcrainmaker.com)

    • Garmin-Joey

      RD Pod wouldn’t have any impact on the overall distance since it just provided running dynamic data. I would encourage you to call and provide activity files so that the altimeter issue can be investigated.

      Like Ray indicated looked at the activities will provide a better idea what might have occurred regarding the distance reported by the two devices.

    • Dennis Piche

      @DCR@GarminJoey – thank you very much for the quick response and all of the great work you do! I have another half in 2 weeks (running with the same friend) so that will be another comparison point as well. Thanks again!

    • Dennis Piche

      Update on my altimeter. I decided to check the elevation graph on my computer (as opposed to my mobile app) and while the elevation is too smooth I can see the big hill on my run. It also shows the elevation low as -233 and high as -24 (elevation is shifted but appears to get the variance right I think… and again way too smooth).

      So it appears that my mobile connect app flatlines the negative elevation… perhaps it can’t handle it?

      @DCR@GarminJoey: The shift in elevation has already been noted. Any idea why the elevation is smoothed out so much? Is it just that way when looking at it on the computer?

      On a side note I looked up the elevation in DC… didn’t realize they were so close to sea level (0 along the river)… or in the sea according to my garmin ;-)

      I am attaching a few elevation graphs so you can see my DC run on computer vs mobile… as well as another run on mobile (with my F3HR).

    • Paul S

      Is there a way of manually calibrating the altimeter? Barometric altimeters only really get absolute altitude right if you can calibrate them, ideally at the beginning of every activity. Garmin has made that mistake again and again, and their ways of automatically calibrating using GPS data have never worked well. The only automatic way that works (the Edges do this) is to tie an altitude to a POI, but I assume that without maps the 645 doesn’t take POI’s.

  117. Donna

    Is anyone else having trouble with Garmin Connect? I have the new 645M and the HR is not tracking on Connect. The steps don’t show on the home page of the app but if I dive deeper then I can see them. The watch, the App and my iphone are all updated on current operating systems.

  118. Josh

    Really good experience so far. Outdoor and indoor runs. Compared OHR with Scosche today while on my treadmill run. Regularly within 1-2 BPM. stellar. Fit is perfect. Looks elegant and sporty. No issues with pairing stryd as a footpod for pace/distance for indoor running. I use GPS for outdoor runs, it’s accurate enough for me.

  119. Adam

    Does anyone know if it can be charged while recording an activity? Such as during an ultra race to extend the recording time past when the battery would usually die. This watch seems like it would work great for me except for the few times a year where I would do 12-24 hour activities and I would rather not have to spend more on a watch just for the extended battery life.

  120. Tomasz

    Hi. Great review as always. Can you tell me, why the Deezer app is not available through the Garmin Connect. I can only download Music through the iTunes but in ConnectIQ there is no Music apps :(. I live in Poland :)

  121. vebs

    Hello All,

    I will be receiving my watch from US b y end of this week. I am little worried based on the negatives reviews pouring in on link to forums.garmin.com
    Runners are reporting lot of issues as well be it WiFi, buttons.. You name it and issues are getting reported.

    Does this 645 is really such a brick? I don;t want to repent on my decision of buying such a costly one.
    Looking for some positive reviews :)

    • TheWombat

      We must be reading a different forum! Yes there are a handful of people who have had issues with the FR645 rebooting during a run, but there are very few issues being posted that I can see compared to a look on the VA3 forum.

      I had WiFi connectivity issues, but they seem mostly to have disappeared. Overall I have found the FR645M to be very stable in the 8 days I have now owned it.

      I have posted positive feedback on the Garmin forum about the FR645M a few times but in summary from my own experience:
      -Excellent step up from my existing VAHR
      -Battery life seems ok – about 4-5 days with my exercise routine – which is what I got from my VAHR
      -Screen is very clear and good compared to VAHR
      -Playing music through BeatsX headphones has been flawless whether running or walking
      -Connectivity to Wahoo Tickr, Tickr X and Cadence meters has worked fine
      -Comfortable to wear, changed band/strap to brown leather and think it adds to the looks
      -GPS lock on seems to work fine, tracked my runs ok
      -Bluetooth notifications from phone seem to work fine
      -Audio alerts when running seem to work fine

      The issues I have found – and to me these are all minor for the way I use the watch
      -Altimeter seems to be a little inaccurate
      -Bluetooth connectivity to phone seems to drop occasionally – haven’t figured out the cause. But overall bluetooth connectivity to phone and GCM iOS has been very good
      -WiFi connectivity issues to home network – I could set up and test connection but then it would fail afterwards. However this seems to have been mostly resolved.

      If you are concerned about whether the watch is ready for you, then I’d recommend waiting a couple more months for a few more firmware updates, however from my perspective I rate it highly both in terms of features and stability.


    • vebs

      that surely helps wombat.
      Actually my upgrade will be from VivoSmart HR+ to direct 645. :) As when I started running never I dream of that within 8 months of time period I will be doing 4 HM and 1 FM. So my current VivoSmart HR+ is short on all aspects of serious running.

      I was earlier almost decided on 935 but the factor which tilted in favor of 645 is the dial size. 935 on my wrist is looks very odd.

      Hope i will not be having any issue. But feels good to see the positive feedback.

      Thanks again.

    • Karen

      I have had zero issues with my FR-645M within the week I got it. I am extremely pleased with the device (I had a VA3 before hich kept freezing). I think as a runner stepping up from a Vivosmart HR+ you will be delighted about all the features :) I

    • Morgan McGuire

      I’m surprised to hear so many bad reviews too – I am super happy with mine. The only issues I’ve had are the altimeter not counting “stairs climbed” correctly, and the temperature being off, but neither of those things are dealbreakers for me and are super minor compared to all the things that work and work well.

    • John Kissane

      First run with the non-music 645 today, an interval session on a treadmill using a stryd footpod. Watch froze after 4k and stayed that way ’til close the finish. Distance was ok but the rest of the data was garbage. Guess I should have expected early versions of the s/w to be buggy as hell as was burned by the 620 in this way as well :(

      I’ve posted it on the 645 forum – link to forums.garmin.com

  122. Thomas B.

    Is there any rumor of updates to Fenix or other Forerunners in the near-term?

  123. austin

    Hi! I’m late to your fabulously detailed postings about great tech gear for athletes. I have a speculative question; I’m really smitten with the white banded Fenix 5 and 5s and am tempted to buy the last boxed one at my local REI. But it seems like the new ones always come out this time of year, so wondering if I should wait and see if the new white (hopefully they’ll have white!) models are improved and have better apps, etc. What do you think? Mistake to buy the ‘old’ one if new ones are coming soon? Are new ones coming soon? Thanks so much in advance!

  124. DanielV

    Hi @Ray, @GarminJoey,

    any updates on the HR issue mentioned in the review (HR on the interval running) or the shifted/errorous elevation figures? I already ordered my 645M, but would love to know if there is something critical with the watch, so I can still return the watch gor the 935 :) …


    • Tomasz

      I just did some 10×400 meters with high intensity. The HR measurements from the wrist sensor are very poor. Hardly, there’s no way to recognize where the interval starts, or where it ends. But the worst thing is that during the 400m i didn’t reach the BPM, that i usually do. I was near to death with 645 showing bpm somewhere near 160 (which is my second zone). Its not looking good. Hope some software update will fix it in future. Now i have to bring back my HRM to trainings.

    • RE: HR issues on intervals in the review

      No, I’ve got it on my list to do another run slightly differently to gather some data for them. Probably tomorrow.

      RE: Elevation shifting

      It sounds like they may have a fix for this in the next firmware update. I don’t have a date for that, but typically we see them iterate pretty quickly after a product rollout.

    • Garmin-Joey

      RE: Elevation

      The Forerunner 645 does not have a manual calibration for the barometric altimeter. The design of the watch is to calibrate this when a 3D GPS fix is acquired which occurs about 30 seconds after after receiving a 2D fix (indicated by the Green Ring and text, “GPS Ready”). There is currently an issue with the 2.40 software where this calibration is not occurring like it should. We expect this to be resolved in the next update.

    • Morgan McGuire

      Thank you for explaining, Garmin-Joey!

    • Paul S.

      Garmin-Joey. you know that hasn’t worked over the years with a wide variety of Garmin devices? The VIRB 360 does it, and it doesn’t work well. The VIRB Elite did it, and it was positively awful; 2200 ft off was the worst, but it was often hundreds of feet off. My first Edge, the 705, initially didn’t have any way of calibration, and until they finally came up with a way (tagging POI’s with altitude) it was often (you guessed it) hundreds of feet off, so much so that I had little scripts to shift the altitude in the TCX files. Initial calibration with GPS data alone just doesn’t work. Any time you have a barometric altimeter, you need to have a way to manually calibrate it. Some kind of UI to do that should be added to the 645.

    • Dennis Piche

      Thanks for the update on the altimeter. While some may wish to manually collaborate I like the idea of auto collaborating. I look forward to the next release.

    • Patrick Craenmehr

      If this is the same auto calibration as on my current vivoactive HR, then it does not work most of the time. But at least the VA HR also has the option to calibrate manually, which I do regularly. I don’t understand Garmin’s position in this. What’s wrong with having both, auto and manual?

    • DanielV

      Any updates on the HR on intervals? My watch should come in the next days :) :( …

  125. John

    This device is the worst implementation to date for Heart Rate Monitoring Cardio Works (Boot Camps, Power Yoga….) that I have seen (Polar A360, M600, Garmin Vivosmart HR, UP3, Samsung Gear S2).

    Initially, I was somewhat optimistic it would do better than my polar M600, as it fits better on my somewhat narrow wrists and was providing similar results for my other HRM during runs, sleeps, and other daily activities. But regretfully, the device seems significantly under report HR when arm muscles are actively engaged – Planks, Pushups….) and it would appear there is significant dampening in the algorithms that also result in under reporting HRM.

    Tomorrow, I will use my Polar OH1, M600 to post benchmarks and show that it is possible to get far better results that this device provides.

    Hopefully, Garmin can fix this because otherwise I am pretty happy with the product (especially the battery life and the continuous HRM).

  126. DanielV

    Thanks for the immediate response. Uff, the interval HRs are so bad? Should I rather cancel and go for the 935? Ray, you msntioned it was not an issue during the first tests…?

  127. Mario


    Is it possible to control music playing by an iPhone from the 645?

    With a 230, I could pause/play/modify volume from the watch. I haven’t found how to do so from a 645 music. This use case is perhaps less relevant now that the 645 can play music. However, for users of non-supported streaming services (like Apple Music), it is a feature that is still required.

    • Mario

      Nevermind. One can change the music source through the music control app in the 645.

    • Garmin-Joey

      You can user the Forerunner 645 Music to control the music player on your phone.

      There is an option in the Music Control that allows you to switch between watch music and phone music. The Source Icon looks like 3 lines with a music note (when set to watch music). It is a phone icon and a music note when set to control music on the phone.

      More information about Music Playback Controls can be found in the following link: link to www8.garmin.com.

  128. AndyD

    I have managed to upload podcasts from iTunes to Garmin Express (they appear on device), but then cannot seem to get them to load on to the 645, or to play. Any ideas welcome please! Could it be that they will only play under a podcast category, which is not present?

    • Garmin-Joey

      Do you get any error when sending the podcast to the 645?

      If not, do you see a Podcast option when you look at Music Source>My Music>scroll down to Podcasts?

  129. John

    Here is an example of Power Yoga Class using Garmin 645 (top) vs Polar OH1 (bottom) and you can clearly see how inaccurate the Garmin and how it “dampens” the results during highly variable heart rate situations.

    • Luis Sánchez

      The problem is not with Garmin accuracy but with OHR dealing with sports that involve wrist flexion/torsion.

      OHR wrist monitors (OH1 or Scosche are not affected as you usually wear them on the arm) are a mess with sports such as tennis, cycling, weightlifting, etc. But not only Garmin, every one of them. I recommend you to check the reviews of other products (Polar, Fitbit, Suunto…) and you’ll see…

      I usually pair my Scosche with my watch when I want to track cross-training, weights, tennis, bike rides or rowing.

    • Sherry

      I have heard so many great things about this Scosche arm band. I am waiting for the newest version to be released so I can try it out. Can’t stand chest heartrates so glad they have an arm version.

  130. Anthony

    Just received 645 music and a bit disappointed that 3rd party music apps are not yet available. Online chat yielded no answers. Has anyone else had better luck regarding ETA?

  131. Eternal Optimist

    Thanks for (all) the great reviews, and the links to CT Europe – who provide my 645M in next to no time. Re wireless headphones, Jabra Sports Coach worked well on left wrist – occasional cut-outs (repeatbly if I let my hand fall to waist/hips when resting (moral: don’t stop :-)) so sorta average. On right wrist no cut-outs at all admittedly only short run (5k ish)

  132. joe

    Hi DC,

    How does the size compares to the 735?


  133. Chris Cooper

    Does anyone know if it’s OK to routinely charge this type of battery in the FR 645M on less than a full cycle (when it’s not close to “empty”)? Maybe that’s a dumb question, but I don’t want to spend this much money for a watch if it’s going to lose its charge capacity after 6 months. Thanks for any help!

    • Kiske

      Lithium-ion batteries and the different variants are completely safe to charge when not empty. What they don’t like is to discharged completely. Most vendors limit how deep we can discharge the battery so most probably you can charge it any way you want as long as you don’t let it sit uncharged and unused for a long time.

  134. Mark

    With iheartradio declaring bankruptcy, do you think you can pressure Garmin to partner with Spotify!?!? You’ve got the clout ;) I would love to see the music feature on the Fenix 6 next year hopefully.

    • It’s not a matter of me pressuring Garmin. Quite frankly they want it more than anyone else. It’s a matter of Spotify wanting any partner at all. After all, they turned down Fitbit too.

      Also note the iHeartRadio news won’t really mean anything. It’s merely Ch11, and the way the deal is structured is actually pretty good news for the company.

  135. Jen

    My issue is I cannot connect to my phone (Droid turbo with 6.01 Android and BT software). Spent a ton of time trying myself and an hour with Garmin. Still can’t get it to connect. :(

    They opened a case file to figure it out but makes it a little less fun for me

  136. Martin

    Hello Garmin Joey,
    Just a quick question: Garmin says that the Skullcandy Method Wireless will be 50% off when buying the 645. How do customers get the discount?
    Thank you

    • Garmin-Joey

      Once the device is set up, either through Garmin Express or Connect Mobile, you will receive a registration email. The discount code comes in that email.

    • Martin

      Hi Joey,
      Wow – that was quick. Thank you and have a nice evening!

    • Donna

      I just tried the code (using the link from the email I received) and it does not work.

    • Hathos

      I tried the code and it lowered the price from $48 to $24. Try copy and pasting it.

    • Garmin-Joey


      If it still isn’t working for you, I would encourage you to reach out to our Product Support team (social@garmin.com). Include the code that you received. Our Product Support team can work with the right internal teams to look into this further to help you out.

  137. Martynas

    Hello DC,
    You can remove IHeartradio from listing of music streaming services for this watch as they have filled for bankruptcy. So only Deezer is available.

    • Paul S

      Filing for bankrupcy is not the same as going out of business. Unless you’ve seen otherwise, I’d assume they’re going to continue.

    • Martynas

      I think that 20bn in debt is quite serious problem for the service to keep alive so I doubt they will survive or someone will buy them for 1$:
      link to forbes.com

    • Article Reader

      From the Forbes article you linked:

      “Just because iHeartRadio has officially filed for bankruptcy, that doesn’t mean that drastic changes are coming, at least not right away. In fact, the radio powerhouse claims in its public announcement of the dealing that it will “continue operating the business in the ordinary course as a leading global multi-platform media, entertainment and data company,” though the future of iHeart is sure to be a tricky one now that it won’t have the power over its own finances as it once did.”

    • Indeed, as Paul as others have noted (including Forbes), filing for Ch11 bankruptcy isn’t really a huge concern. The way and concept of bankruptcy’s in the United States is a bit different than many other countries. So for those outside the US it might be a bit confusing.

      Essentially you’ve got two buckets, named after the bankruptcy code sections – but are very commonly simply called ‘Chapter 11’ and ‘Chapter 7’, virtually any American would know those two phrases if heard on the news – though they might not fully understand the nuances:

      Chapter 11: This is basically where you declare yourself unable to pay various debts and you go into a court where they approve/deny financial aspects. It’s sorta like having your bank accounts locked. Countless massive American companies have filed for Ch11 (including many airlines). You can see a small sampling of this list here: link to en.wikipedia.org

      Oftentimes companies will stay in Chapter 11 for a long period, such a year or so. For most consumers, it’s business as normal. Whereas for vendors, it gets a bit sticky. If you do some reading about the iHeartRadio deal, it’s actually a bit unique in the pickle they were in whereby they have a pretty viable chance of making a solid comeback after the debt restructuring.

      Chapter 7: This is the one that means bad stuff is happening and the company is effectively closing. Assets are liquidated and employees are laid off. It’s over.

  138. AndyD

    Hi Joey,
    Thanks for your response, regarding my not being able to play podcasts.
    The podcast appears on the FR645 in Garmin Express (Mac) once uploaded,
    but when I go to the device controls: my music > podcasts. I get the message no podcast available.
    Do you have any ideas why this podcasts won’t play.
    Thanks once again.

    • Garmin-Joey

      Hi AndyD,

      Not sure why the podcast isn’t showing up. Something that we would want to look at in more detail. I would recommend sending and email to our Product Support team at social@garmin.com.

      Information such as:

      Specifics about your Mac version, Garmin Express version, screenshot of Garmin Express, and attaching the Podcast file would be helpful in investigating why this has occurred.

  139. Hathos

    I went ahead and bought the device from Clevertraining using the DCR VIP plan. I have to say that I’m really impressed with the device so far, and just in terms of appearance, it is a huge step up from the FR 235. I look forward to your review on the Scosche 24, as I am eager to try out a heart-rate monitor for more accurate data with sprinting, but I’m not quite sure if I’ll like a chest-strap, especially with what everyone says about them.

  140. JP

    Sadly iHeartradio subscription (of any kind) is not available in Australia. I have written confirmation from iHeartradio in the US about this.
    It really surprises me that Garmin Australia’s marketing or product team have not done their research before advertising this feature on their website. It is a massive drawback on one of the watch’s biggest selling point – ability to store offline cached playlists.
    Transferring mp3 files to a music storage device was done 10 years ago.

  141. Kerri Muldowney

    I never received any email when I got my 645 music so never got any half price code for the earphones

    • Garmin-Joey

      If you don’t see the email in spam/junk mail folder for the email address used for Garmin Connect, contact our Product Support team (social@garmin.com) and they will be able to help out.

    • Kerri Muldowney

      Sorted, got the code, ordered the earphones, thanks

  142. Jennifer Fischer

    I need a new watch band. Maybe a Velcro one so doesn’t dig into my wrist

  143. John Kissane

    Never had an activity tracker before but is this level of craziness normal? The watch thinks I’ve climbed 91 floors (so far) today, real number is probably < 10.

    Doesn't really bother me as I just wanted it as a running watch but why even bother tracking floors if it's this inaccurate?

    • I haven’t had it happen in a while on a Garmin device, but when it did happen it was triggered by:

      A) An elevator, whereby it thought I was walking
      B) Escalators (large ones) where I was also walking up

      The way the tech works is that it uses the baro altimeter to determine elevation gain, and matches that with whether or not you’re walking. In theory this cancels out things like elevator rides or flights, because you’re not walking at the same time. There’s obvious some other algorithm magic too.

      But inversely, if it’s counting steps for some mundane activity (like driving) and your also ascending, then it can trigger it. I’d look at the daily chart and see what time of day the majority of those stairs were racked up to see if there’s a clue on what activity is causing it.

    • John Kissane

      Thanks for the info, no escalators, elevators or driving in my life on that day at least. Activity wise there was ~26k of running (to, from & taking part in my local parkrun) and then walking around town picking up groceries.

      Use the watch for the first time in a running event on Sunday, it measured 41.84k for a marathon so guess still some work to be done on the GPS side, at least it’s not as bad as the 620 when it first came out.

    • John Kissane

      Perhaps this will make things better!

      Forerunner 645 changes from 2.40 to 2.50:
      Added Trail Run
      Improved Floors Climbed Algorithm
      Improved Absolute Elevation Calculation
      Improved Rep Counting UI
      Updated Translations
      Changes to Support Factory
      Numerous Other Fixes

    • Kerri Muldowney

      I’m on 2:40, have you had this update?

    • Garmin-Joey

      Most of the recent Fitness devices will get a ‘phased roll out’ of any new software updates. Currently the 2.50 update for 645/645M is only available to 20% of users.

      The roll out tends to roll out over a 24 hour period.

      We update this thread as the software is rolled out: link to forums.garmin.com

  144. Sunny

    …express crashed after loading 69 music files, retry and loaded first 10 really fast, now I can only imagine watching paint dry would be worse, 84 of 188, 8 minutes left…and crashed, the dialog for loading songs closes and your are left on the my music page not knowing what’s transferred. Pretty poor.


  145. Dennis Piche

    RE: Deezer: Trying it out and so far I like it. Great content including podcasts and I think I will like their Flow feature. While most friends are on Spotify I might be able to use Deezer as my goto if it integrates well. We will see next month.

  146. Josh

    Ive actually had continued good luck with the OHR on this device (645 NON music), using stryd for pace and distance while on the treadmill, and using STRYD for pace and GPS for distance while outside. What I dont understand is why post run when looking at my HR for last 4 hours, the high of the day is never what the watch says. I remember this being an issue on the 935 as well. Garmin Joey, Ray, thoughts?
    Vibration strength is much less intrusive than my 230, and also quieter. Screen is quite bright although I’d love to be able to make it brighter like you can the 935.

  147. Morgan McGuire

    A weird glitch (I guess?) I’ve noticed. When I go for a run, the time of day on my activity summary later is correct. But when I do any other activity, the time of day is way off. For instance I did elliptical at 9:15 am and the summary said it was 4:15 pm. Same for HIIT, 10:15 am but summary said 5:15 pm. Any idea what that could be about?

  148. Chris Cooper

    Looks like Garmin Pay is now available. Not sure if it works. I loaded my card info on there and will test next time I go out.

    Also noticed it’s way easier to transfer music onto the watch using Windows Media Player with my PC than using Garmin Express on my Mac. My PC is a work computer and I’m restricted from downloading Garmin Connect or iTunes. But can transfer my music stored on a USB to Windows Media Player, then to the watch easily using MTP.

    For some reason Garmin Express is wonky on my Mac. Perhaps an issue with the fact that its an old Mac with an OS that hasn’t been updated in a couple of years? But either Garmin Express will crash before connecting to my watch (concurrent with when I attach my watch to the charger prior to opening Express, but not the other way around) or it won’t load the music on to my watch once I select an iTunes playlist? Anyone else have these issues? Kind of a minor problem, as it can be worked around, but would love to know how to get Express to work like it should on my personal computer, and not work computer.

    • Paul S

      They just pushed out an update for Garmin Express on macOS. The current version is

    • Mr. T

      Absolutely no issues with Garmin Express on my Mac. In fact, it was very easy to transfer music.

      I have an older Mac Mini but am running MacOS 10.13.1 Also using the latest version of Garmin Express. I have 4000+ mp3s on my mac so I really only have one option.

    • Kerri Muldowney

      My banks not added yet, just wondered what bank you use

  149. Matt

    Can this 645 or another Garmin watch track your body’s temperature? Or do you need some external sensor? Thanks.

  150. Elsie

    UK based folk – Sports Direct are offering 20% off ANYTHING bought through their app at the moment. It’s only meant to be for things up to £200 but I just paid for the 645 Music and entered the code and it took £80 off so I got it for £320, with then £7 added for next day delivery.

    They might correct this mistake so if you’re thinking of ordering, there’s an option.

  151. Kerri Muldowney

    Has anyone managed to add a bank card to the Garmin pay wallet in the UK? I’ve tried a Halifax one and it says it’s not supported, just wondering if any are?

  152. Shawn McClelland

    Had the watch a couple weeks now, the last couple days it seemed to be losing bluetooth connection to my phone. And (probably related) this morning after a 100% charge it completely died in about 2 hours – I looked down and it was blank, tried turning it on, it showed low battery and wouldn’t come on.

    Anyone else have this?

    • Mike r

      Yes same issue here

      I’m also now not able to pair it to my iPhone or connect to WiFi…. reinstalled the Garmin app with no luck any other suggestions??

  153. Elsie

    I had my order confirmation a couple of hours later saying it was ready for the courier to collect and I’d receive another email once they do. It’s now 9am on the day of delivery and I’ve had no email, so I’m not optimistic.

    I did always know that saving £80 may come with a hiccup or two…

    • Robert Scriven

      Mine said that, now says 20/03/2018 09:21 Due to be delivered today.

      Im sure i selected DPD as well, but says hermes.

    • Elsie

      I should have paid the extra £1 for “Premium Next Day Delivery” perhaps…

      Maybe premium means it will actually happen.

    • Elsie

      Just had a text from Hermes saying they have it and its on its way! Still no email from Sports Direct. Fingers crossed

    • Robert Scriven

      Mines come :-)

    • Elsie

      As has mine! Love it so far, such a more comfortable fit than the 235 which I had previously (and loved also).

    • G Man

      Do you also have a 235 Elsie? Can you do a side by side comparison photo of the two as debating between them!

      Concerned 645 in steel/silver may look a little feminine and would appreciate any thoughts

    • Elsie

      Yes I do. I don’t find it feminine (I’m a man). I think it looks quite a lot more professional for wearing day-to-day. It’s a lot more comfortable, particularly because the heart rate monitor doesn’t stick in. But also because the strap is nicer and it’s lighter.

      You’ll also notice the strap is slightly shorter. I like this as it gives me a more snug fit without a load flapping about.

    • Elsie

      This is the profile side on comparison between 645 and 235. I’ve tried to show the protrusions of the heart rate monitors. Hard to see with my poor camera skills but basically the 645 fits a lot flusher and nicer to the skin.

    • G Man

      Many thanks for responding

    • Appears the 645M is smaller despite it having a larger screen. Will order ASAP

    • Nico

      Elsie, I too have the 235 and its been a great watch apart from the poor clarity of the screen. How do the 235 and 645 screens and back lights compare? The poor screen quality of the 235 is really the main feature i would trade up for. Please let me know.

    • Elsie

      The 645 has a much clearer and cleaner screen in my opinion, with the white background actually being white rather than a dull grey-yellowy colour. But it’s hard for me to comment whether its better enough to trade up for. I probably wouldn’t have for the screen alone, although I didn’t really have a problem with the 245. And I’ve not actually played with any of the more expensive watches so don’t know how this one compares to those. It’s very crisp and much bigger as it’s a full circle rather than having top and bottom cut off.

      Everything else feels like an upgrade though. So the screen, the durability, the strap, the buckle. They all feel better made and more secure. And you forget you’re wearing it, which is something I rarely did with the 235. I was able to sleep wearing it last night and I used to have to take the 235 off because it got too uncomfortable and sweaty. Again for any of these things alone I wouldn’t have upgraded so soon, but combined they’re great.

      But also the software feels newer and quicker (as you’d expect). They’re all mainly minor things but as a whole it makes me feel very pleased I upgraded. Especially since my 235 is now on eBay and the current bid is only £30 less than I paid for it 14 months ago.

      The main reason I upgraded was for the music, as my trusty old iPod shuffle has finally given in, and I’ve recently got annoyed with headphone tangling. I’ve not had chance to test out the music yet as I don’t have any bluetooth headphones (they’re on the way – expensive month!) And I haven’t been out for a run with it yet, although I’m trusting that it will be a similar experience to the 235, with a few extra data screens to get my geek-mode excited.

    • Nicos

      Thanks Elsie, I’m glad to hear the screen is clearer. How is the back light? any brighter? The 235 was awful.

      A running mate of mine has the Fenix 5S which is the smaller one, but the screen is a bit too small although clarity is better than my 235.

      Think the 645 looks a little more ‘premium’ compared to the 235 which always looked a bit cheap and plasticky. However it performed really well.

    • Sherry

      I have also owned the 235 and now have the 645. I did have the Fenix 5s briefly until the 645 was announced and I returned the 5S. The 645 screen is even better than the 5s. The 5s had a resolution of 218×218 while the 645 has a screen of 240×240. I forget what the 235 had but much lower than either of these two. I love the screen on the 645. The best I have seen so far. Backlight is great too. I only use the backlight after sunset but it is a nice bright color.

      I bought the 645 for the more detailed running dynamics and the music. So far it has been great. I wear it 24/7 as it is very comfortable. 5s was very nice but a little on the heavy side. The 645 is very light and I think very stylish.

    • Nico

      Thanks Sherry. I like what you have just said and think i might well go for the 645.

  154. Kerri Muldowney

    Just been on garmin forum, there are a few of us that have contacted uk banks re supporting garmin pay, all the major banks have no plans to support, some have no idea what garmin pay is, so if you are buying this device for the pay function then you may be in for a long wait.

    • Robert Scriven

      It would have been easier for them to have put Android Pay and Apple Pay on, id say those two have about 95% market share!

  155. Jennifer Fischer

    Two questions ..
    1. How do you turn the music off? Do I have to turn off headphones? I didn’t see an off button

    2. I created a workout on Connect, but it will not download to my watch. I click send to device, but nothing happens

    Any help would be appreciated

  156. Kieran B.

    I ordered mine on Clevertraining.co.uk 10 days ago and I’m still waiting for it. Has anyone received their’s from Clevertraining.co.uk yet ?

  157. Sherry

    Any more news on the IHeartradio app? It has been 2 weeks since this was posted. Waiting to try out the music feature on this bad boy.

    • Mark

      I think Garmin is hoping if they ignore it long enough, people will stop asking for updates when it will be available.

    • Sherry

      Lol, you could be right! What’s the deal

    • Garmin-Joey

      Sorry for the delay in responding to this comment.

      We are working to release the iHeartRadio app. We are targeting a launch early next week for this app.

    • Sherry

      What delay, that answer came pretty quick! Thanks for responding Garmin-Joey! I am looking forward to it.

    • AndyD

      Hi Joey,
      Do you have an ETA on the Deezer aop, as I signed up already?

      Thank you for great work on Both the hardware and software, which makes it such a compelling upgrade option to runners.

      Finally a beautuful watch for runners!

      Andy d

  158. Sean Matthews

    Not looking good for UK banks. I’m one of the ones on the Garmin forum (Wepre Runner) and have had little luck trying to get support thus far.

    • Elsie

      It’s hardly a surprise though is it. Integration will come at a cost for them, and hardly any of their customers (a tiny tiny percentage) will have the capability to use it.

      It took a lot of banks up to a year to embrace Apple Pay. Garmin have a fraction of the users and only a fraction of Garmin’s users can even use it.

      I have a 645 and want to use Garmin Pay but I can’t see what’s in it for any banks. It will cost them to implement and not implementing isn’t going to lose them much custom, if any.

    • Elsie

      Also bear in mind that the banks will know that more or less EVERYBODY who wants to use Garmin Pay (who is pretty much hardly anyone in the first place), will already have the ability to pay digitally through iPhone or Android. So they’re not alienating anybody at all by not introducing it.

      Garmin may need to incentivise banks to join. Hopefully they are.

    • Robin

      I live in NZ. My Bank is ANZ which operates across Australia and NZ. The Australian arm has released it but not the NZ arm. Here in NZ, only two banks have implemented Apple Pay (I’m not sure on the Android side of things) and one only recently.

      Elsie – I agree with your comments. As I think Ray mentioned, Fitbit are struggling with getting the banks on board. Garmin are probably a smaller player in the wearables space so will struggle even more.

      In saying that, I don’t have any skin in this game yet and won’t for a while as I just bought a 935.

  159. Rene

    Thank you for this great review. Had a doubt about which (my first) running watch I had to buy. This review made it clear to me. First, I was looking at the 235 but the accuracy of the heart rate monitor was holding me back. The 645 has a new heart rate monitor and it has music. My wife has the TomTom and I do not like that one. I already use other Garmin GPS devices and activity trackers so a running watch from Garmin would we the next step.

    The only thing is the availability. The second week of April my running clinic will start. The 645/645M are not available yet in stores (stone and web) in the Netherlands :(


    • Tyas

      Check with your local running store. Running stores in Maastricht (Lopers Company) and The Hague (Run2Day and De Hardloopwinkel) have the 645 in stock.

      I just bought mine (black music) online at Sportsdirect, with 20% discount by using their app instead of the website. Ordered tuesday evening, delivery scheduled for tomorrow (friday). Anxiously awaiting my new toy.

      Don’t know about availability of music vs non-music, and for cerise/sandstone, but the black music version is readily available.

    • Jeff N

      I ordered mine (645M) directly from Garmin on their website. Placed the order Tuesday, got a shipping notification yesterday and it appears I will have it tomorrow or Saturday.

  160. sue

    Has anyone found the bluetooth connection to iphone a bit buggy?, mine does sync , however it starts to sync then disconnects then connects again, also sometimes in the iphone’s bluetooth settings its connected , but the app says its not sometimes have to disable and re enable bluetooth on the phone to get it going again.
    I don’t have this problem with the forerunner 935
    Just wondering if its a bug that might be fixed , or is it my watch is faulty
    everything else works perfect including music playback through BT headphones

  161. Brian Free

    Out of curiosity, what purpose does the Gyroscope serve on the Forerunner 645?

  162. Mark R.

    Clevertraining.co.uk has just shipped my 645. I can’t wait for it.