How calorie measurement works on Garmin fitness devices

There are few topics that cause more confusion, intrigue and general ‘Huh?’ in the sports world than calorie burn.  While many runners or cyclists often estimate calorie burn (and thus cookie allocation metrics) using borderline sketchy back of the napkin calculations, there’s also a significant portion of the population that looks to use their Garmin device to determine calorie burn.

The challenge that many folks have found out is that different Garmin devices produce different results, and sometimes – even different results for the same person.  Further, a specific device can even product different results for the same person dependent on how it’s configured.

So, I set out to put together a bit of the definitive guide to calorie calculations on Garmin fitness devices.  Back when I was at the ANT+ Symposium in Calgary I sat down to start the conversation with the Garmin team there.  Then more recently last week I met up again with the Garmin fitness team to talk through all the painstaking details.

The Main Methods

As you might have guessed, there are actually a number of ways in which your Garmin device will calculate how many calories you’ve burned.  And not unexpectedly, the accuracy level varies based on which method you use.  Some methods offer a rudimentary guesstimate, while others are based on scientific testing that’s then imported into your device to get far more accurate results.

So, let’s walk through each of the six major methods, starting with the most accurate, and working our way down the list to the less accurate (the last option, Kilojoules, isn’t really ‘less accurate’ per se, but different…more in a moment).

1) New Leaf VO2 Test Profile: This method requires testing at one of a number of New Leaf testing centers around the country.  New Leaf is actually a 3rd party company that’s developed a pretty comprehensive way to determine calorie burn based on VO2 tests that are done.  The tests are not terribly unlike your common VO2 max test, and involve you being hooked up to tubes and wires.  The tests though are sport-specific, meaning you complete a running test to allow the Forerunner to determine running activity calories.  The tests don’t cross over, but there are tests available for running, cycling and elliptical.  Once a test is complete you can download your ‘profile’ into your Garmin device to get the most accurate calorie burn metrics when combined with a heart rate monitor.  I’m looking to get a New Leaf test done and put together a post or series of posts on the experience and accuracy I see.  Here’s the list of current devices, and levels of compatibility.

2) Firstbeat Algorithm (Current – 2nd Generation): The Firstbeat algorithm is the most accurate Garmin device calorie measurement that can be done without external testing.  But it’s actually not developed natively by Garmin.  It’s developed by a Finish company (Firstbeat Technologies) that has its roots in calculations around Olympic athletes, specifically Nordic skiing.  Their calculation uses  user inputted variables including gender, height, weight and fitness class.  It then combines this data with heart rate information from the ANT+ heart rate strap.  Specifically, it evaluates the time between heart beats (beat to beat) to determine estimated MET (Metabolic Equivalent), which in turn is used determine actual work expenditure.

This makes the system one of the more accurate non-invasive options (read: doesn’t require a laboratory), within about 10% accuracy.  Firstbeat has published a fascinating white paper detailing the technology and accuracy rates.  This little snippet below though helps to show where the technology lies accuracy-wise – with it being right in the upper-middle compared to full-board lab operations on one end, and ‘distance/time’ calculations on the other end (click below to expand picture).


Finally, this metric also ‘learns’ you as an athlete on a given device.  Meaning, over time it has a weighted algorithm to note changes in your fitness level and adjust calorie burn accordingly.  I asked how ‘friends and family’ using a device might impact this.  They noted that a single one-time use wasn’t weighted heavily enough to make a difference, but that obviously a couple sharing a single device would see less accurate results (both due to the profile information being incorrect 50% of the time, as well as the ‘learning’ aspect being off).  It also should be noted that the second-generation of the Firstbeat algorithm is only applicable to running currently, and isn’t used in the cycling products yet.

3) Firstbeat Algorithm (1st Generation): This is essentially the same as the above noted algorithm…except just slightly less accurate.  This first generation algorithm is used on devices prior to this year, which are detailed in the below tables.  Like any product, technology or concept – the calculations have evolved and are made available in its most recent incarnation on Garmin’s most recent devices.  One interesting tidbit is that they found that while this 1st generation algorithm worked really well for newer runners, it was less accurate in more advanced runners – hence some of the updates seen in the 2nd generation.

4) FR60 Heart Rate Algorithm: The FR60 non-GPS running watches have a proprietary heart rate based algorithm that’s used when a heart rate strap is enabled.  The primary driver of this was to remove the dependency on speed/distance that’s typically associated with a GPS unit (since the FR60 is not GPS-based).  The Garmin engineers describe this algorithm as a classic heart rate based calorie burn calculation, with virtually no extra ‘fancies’ tossed in to make it significantly more accurate.  There are no plans to evolve this one-off algorithm to other devices (including the next version of the FR60), nor to port either Firstbeat to the FR60.

5) Speed/Distance Algorithm: This is the most basic method of determining calories, as it is only used when a heart rate strap is not enabled/used (default). Given the lack of heart rate data, the unit will simply use speed/distance, as well as the weight you entered in the device setup.  The reason this is less accurate (65-80% accurate) is that it can’t differentiate how much effort you’re expending to travel a given distance – which while less important for running, is quite important for cycling.  For example, if you’re coasting down a 7 mile descent, you’ll burn virtually no calories compared to ascending the same mountain.  This speed/distance algorithm does not consider or evaluate the impact of elevation change – primarily due to concerns the team had about relying on GPS-based elevation to determine calories.  They also reasoned that while the Edge units had barometric altimeters, it was better to focus on heart-rate based calorie burn, as opposed to simply expanding the ‘guesstimate’ that the speed/distance algorithm is.  Finally, note that if you wear a heart-rate monitor/strap – speed/distance are ignored, and instead one of the other above (more accurate) methods are used.

5) Power Meter to get Kilojoules: While not technically calories, the kilojoules is a unit of work, and thus is a method that some folks may use to judge how much effort was expended on a given workout.  This method is only available on units that support power meters (Forerunner 310XT, Edge 500/705/800), and requires a compatible 3rd party ANT+ power meter (such as a Power Tap hub, Quarq Cinqo, SRM, etc…).  This isn’t less accurate, but rather a different metric than straight calories.  You can convert from kilojoules to calories.

Finally, it should be pointed out that the overall philosophy of the team is/was to get folks using heart rate straps if they want accurate calorie metrics.

Device Breakdown – Running/Multisport

So now that we’ve gone through and covered the main methods for calorie calculations, let’s break it down on a per-device basis.  We’ll start off with the running and multisport related devices.  You can click to expand the chart and get a full view that makes it a bit more visible.


As you can see, the most recent devices (FR210/FR410) have the most up to date calorie metrics – primarily being the 2nd generation Firstbeat Algorithm.  However, many devices support the New Leaf test, almost everything except the FR205, which is simply because it doesn’t support a heart rate strap.

Device Breakdown – Cycling

Next up is the cycling side of things.  You’ll see that again like the running devices, the newest devices – such as the Edge 500 and Edge 800, have the most recent calorie calculations available.


As you’ll notice, the Edge devices also add the kilojoules power meter option, for those with compatible ANT+ power meters.


Device Master Sheet

And finally, one master sheet of all devices in a single table:


Heart Rate Straps

Given so much of the the calorie calculations is dependent on a heart rate strap, I should point out that any ANT+ heart rate strap will work when it comes to gathering heart rate data that the Garmin devices can use.  However, there are a few different Garmin-made ANT+ straps out there to select from.  The three that are available today are:


1) Classic Garmin Heart Rate Strap: This is the most common version, and also been around the longest.  It features a plastic portion of the strap that reads your heart rate, while the remainder of the strap is fabric.

2) Pre-2010 Premium Heart Rate Strap: This strap version came out in Spring 2009, along with the Forerunner 310XT.  It features a fully fabric band all the way around, with snap-on connectors holding the transmitter portion to the fabric.

3) 2010 New Premium Heart Rate Strap: This version came out in August 2010 alongside the Edge 800, and is now shipping with all premium heart rate strap units (i.e. FR310XT, Edge 800, etc…).  This one aims to resolve some of the spiking/dropout issues noted in the pre-2010 version.  In my testing over the past few months, this seems to resolve about 95% of the spiking issues that I’ve seen.  This version will be available for individual purchase, but an exact timeline hasn’t been fully finalized.  Note that I asked if there was a better name for the newest strap besides “New-new Premium Heart Rate Strap”, and the team hadn’t really come up with a good name to use externally.  So, for now, I’m going with 2010 New Premium Heart Rate Strap.

In general, remember, if you’re having problems with heart rate strap readings, be sure to check out both of my posts on the subject – first part here and part two here.


There’s no doubt that the Garmin fitness devices offer a plethora of calorie calculation options.  Before I started looking into this I would have said that there were too many options, however, after understanding the different options better – and the differing levels of accuracy each one offers, I have a better grasp on why there are so many different ways to calculate calories.

As you can see, in many ways – it ends up being a matter of how much effort (or perhaps time/money) one wants to invest in the solution to get the most accurate results.

(Final note – Thanks to the Garmin Fitness team for their time in answering all the questions and detailed specifications of each device and calorie metric type)


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  1. Given that I don’t live in the US, and also don’t know much about the supposed accuracy of New leaf setups at gyms as opposed to anything produced at a normal sports science lab, do you know if there is any way of putting in or editing any metabolic profile data manually?



  2. Anonymous

    Do you know if Garmin has any plans to allow devices such as the FR310XT that use the Firstbeat 1st gen algorithm to be upgraded to 2nd gen algorithm?

  3. tms

    Great article – just picked up an Edge 800 and from what I’ve seen the kcal estimates are a massive improvement over the 705. The almost laughable readings the old Garmins produced was the main thing keeping me using my Polar for running, but from the looks of it they’ve made some big steps forward on that front!

    You mention that the Firstbeat algorithm uses beat-to-beat measurements, so I was wondering if Garmin’s HR strap actually delivers this data (and discards it) or if it’s just reconstructing it from the second-by-second readings? I always figured that the reason Garmin didn’t provide R-R data like Polar/Suunto was that the ANT+ profile didn’t support it – but if that data is being delivered to the head unit it’s a bit of a shame if they’re just throwing it away.

    Also, do you have any thoughts about the accuracy of these algorithms compared to that of their competitors? Polar and Suunto have been using their own R-R heart-rate based caloric calculations for a while – so I’d be interested to hear how these compare?

  4. interesting and great post. i’ve always wondered how those pesky calorie calculators work. i’d also want to know how garmin compares to the competitors as well as how these calculations compare to machines at a gym

  5. Anonymous

    Do you know if they calculate net calories by subtracting out a base metabolism rate?

  6. @TMS: Suunto have been using firstbeat with the R-R data on their high end watches for a while. One thing I really miss from my T6 in my rowing days is the wealth of info I could pull out from workouts relating to oxygen debt, calorie usage etc. The TE scores were pretty useful once you got things well enough calibrated too. Certainly good enough to help guide things when I was doing less structured training in the off season.

    On the other hand with the 310xt I get decent gps and the facility for power going forward, so that was the trade off for triathlon type training. The 310 certainly doesn’t store all the R-R info which is a shame as it has the space. I would have thought the ant+ protocol can cope as the suunto watches use plain ant to receive their data. Kind of interested as to whether the 310xt actually does handle r-r data internally as then in theory it should be possible to save it and use it for detailed analysis based on variability in intervals…

  7. Great post, as always!
    Do you know what kind of calorie measurement SportTracks 2.0 uses? When I download workouts on the program, it changes the value of the calories determined by my FR305.

    Thanks for your work! Ciao from Italy!!

  8. I had no idea there were two version of the premium soft strap heart rate monitor. Any idea if the new strap with less bugs can now be purchased online through Amazon? Feel free to toss out a link we can use so that you can collect on the affiliate referrals =)

  9. Bruce

    What calorie count method does the 305 use? The article says New Leaf, but I couldn’t find much information on what it is and how accurate it is when doing normal exercising. Thank you. Bruce

  10. Anonymous

    Great article – I had emailed Garmin with a question about the calorie computation for the 405CX versus the 305 and they referred me here!

    Unfortunately, I’m getting really lousy calorie results (405CX says calorie burn is about 1/2 what it was on the 305 and even less than what tables based on time/distance/weight say, so that with the bezel issues have made me decide to return it…

  11. Anonymous

    The cycling chart in the article looks to say the Edge 305 only uses speed/distance/weight to calculate calories, and not the HR strap. Can someone confirm if that is really true?!?!

  12. Ash

    Hi Ray

    The calculation table shows that the 800 can use both First Beat and Power meter for calorie calculation. But which takes precedent?

    If I use both HR and Quarq, which will it be using for the calculation?

  13. Hi Anon-

    RE: Upgrade 310XT to 2nd gen algorithm.

    No, I asked, no plans.

    Hi Anon-

    RE: Removal of base metabolism rate

    I don’t believe they do, based on my understanding. I’ll save it for the next time I chat with them.

    Hi Andrea-

    RE: ST Calorie calcs

    It uses a simple distance algorithm based on ‘standards’ for different activity type

    Hi djpfine-

    RE: New premium soft strap version buy standalone

    It’s not yet on Amazon, but is available on Garmin.com

    Hi Anon-

    RE: Edge 305 calorie not using HR strap

    That’s correct, and the Garmin engineering team validated all these charts pre-publishing.

    Hi Ash-

    RE: Edge 800 power meter calcs

    The power meter calculation method I’m referring to is kilojoules, not straight calories – and is seperate from calories in the traditional sense. The detailed description is above. Thanks!

  14. Anonymous

    Thanks for the interesting article.
    The table you posted indicates the FR-305 uses new leaf, which requires only heart-rate data. However, I don’t get a caloric statistic when I train indoors (spinning). Any ideas?

  15. Anonymous

    I was referred to this site by Garmin Support. OK. Still – I rode for 2 hours, covered 37 miles and my brand new Garmin 800 says I burned 350 calories. This was a normal ride, 1100 ft of elevation gain and relatively fast. 350 calories! NOT! I estimate (via the old 705) that I burn just under 1000 calories per hour on my usual rides. That said – the 800, in my opinion, is about 10% accurate – 90% off. I like the 800 – but am not a fan of Garmin Support. My 705 lasted 19 months before it bought the farm – the 800 better last longer. Any ideas from anyone on what is going on here? ken@bikerfive.net

  16. my 410 seems pretty wacky compared to the FR60 that it replaced (which is being used by my wife now), wondering if it’s best to try another..

  17. This comment has been removed by the author.

  18. This comment has been removed by the author.

  19. Do you have any information how the Garmin products compare to Polar products for calorie calculations?

    There’s an interesting debate about calories burned on the Garmin 405CX forums: link to forums.garmin.com

  20. Anonymous

    I’m not clear on the calorie calculation method for the FR305. Are you indicating you have to get a New Leaf VO2 test performed to get the FR305 device to calorie count based on HR, otherwise the unit defaults to time/distance even if you are using the HR strap?


  21. From the charts, looks like the EDGE705 calculates calories using only speed/distance, regardless if you have an HR strap or not… That explains the bad readings I get when I’m using it.
    I also have a powertap, so I usually get the calories count from the powertap software instead of the garmin software. Would that be the best way to do it, or do you have a different recommendation ?
    For my indoor workout, I use the Suunto memory belt, and that seems to be very accurate (and also calculates Traing effect)

  22. Kel

    I also am wondering about the FR305. I haven’t had a test done so I’m guessing it just uses the speed/distance thing… So what’s the point of the heart rate strap then? I have an old, plain jane HR monitor and it calculates calories based on the heart rate over time.

    However when I use my 305 indoors with the GPS off, I can see it’s counting my HR but I just get a 0 for calories. However if I then plug in the data from the bike for distance, SportTracks comes up with a calorie numbers. Of course it’s way off from what the actual bike told me but at least it’s something.

    Maybe I’m just missing something?

  23. Apparently the new premium HR strap can make a huge difference.

    I first bought a new 410 and used it on 9 mile run with my old style monitor strap. It said I burned 805 calories. Didn’t like the touch bezel on the 410; the 210 went on sale; so I exchanged at REI. Same 9 mile run (actually run at a faster pace, but nearly same recorded heart rate) with 210 and new premium strap that came with it, yielded only 498 calories.

    I assume the 410 and 210 use same calorie count technology. Again, the new model strap I used with the 210 showed an average HR of 126 while the old style strap coupled with the 410 had my average HR at 127 (despite my running 30 seconds per mile faster the day I used the 210). I should also state that my user profile settings were the same with my height, weight, age, and “lifetime athlete.”

    So, same user profile, same route and distance, similar weather conditions, nearly the same measured average HR; yet huge calorie count discrepancy between 410 with old style strap vs. 410 with new premium strap. Does this make any sense at all? I must say less than 500 calories for a 9 mile run at a pretty good pace (for me) is damn disappointing.

  24. Correction: at end of my post, I meant to say “huge calorie count discrepancy between 410 with old style strap vs. 210 with new premium strap.”

  25. FYI, I just installed the Update to 2.90 on my Garmine 310XT. According to their release notes, it has been upgraded to 2nd Generation Firstbeat since 2.70

  26. I have the same doubt of the Anonymous in post 20.

    I simply don’t believe in the calories results in my FR305, especially on the bike.

  27. Hi All-

    RE: FR305

    Indeed, the FR305 really does NOT do HR based calorie metrics unless you have a New Leaf test done. I’ve confirmed this again with Garmin, and this can be confirmed in multiple places on the Garmin Forums:

    link to forums.garmin.com

    With a New Leaf test you can then use the HR starp to get accurate calorie burn on the FR305, but otherwise it’s just speed/dist/weight calcs.

    RE: New Strap vs Old Strap

    There’s no difference between the two straps from a calorie basis – unless the straps were giving incorrect readings altogether. ANT+ straps don’t do calorie calculations, nor can a Garmin unit tell the difference between a soft strap and a classic strap (or even two generations of soft straps). The ANT+ Device Profile doesn’t contain the ability to transfer calories (or store weight information). That said, looking at the two devices, there could be something else at play here – including perhaps just a bug.

  28. Tim

    Just wanted to note that the 310xt seems to have been updated to 2nd generation firstbeat as of software 3.7.

  29. Josh

    I noticed that you mention that the edge 500 works with the new leaf test and your charts show this to be the case. However, the linked chart on new leaf’s site shows that it isn’t compatible with the test. Do you know which chart is correct?

  30. Anonymous

    Is there a web site or application that can recalculate calories burned from TCX file?

  31. Can you say how the Timex (Timex Run Trainer ans Timex Global Trainer) and Polar (RCX5) watches that you reviewed do the calories calculations?

  32. rgabba

    Hi Ray, greeting from Italy, thanks for your reviews, very useful.
    I have a FR60 for my indoor training (treadmill and spinning mainly) and a brand new EDGE 500 with speed/cadence sensor for cycling.
    I have tried FR60 and EDGE together in a short cycling training and they have gave me a different result about calories; edge 728kcal/h, FR60 1091kcal/h !!! Both were paired with the same heart rate monitor strap and speed/cadence sensor.
    What do you think about it? Which is most accurate? Both use HR for calories calculation, I know with different algorithm but I can’t understand so different results.

    • Datz

      I just moved from the FR60 to the 310xt.
      My cal counts were the exact same as yours, and I’m wondering the same thing.
      I too am using the same HR and cadence monitors.
      Quite a big difference.

  33. Oliver


    I have a Garmin Forerunner 405 and use the Classic Garmin HR Strap.

    According to the Device Breakdown chart the calorie calculation method for this device is either #1″New Leaf VO2 Test Profile” or #5″Speed/Distance Algorithm”. I do not use #1. The last sentence under #5 states “Finally, note that if you wear a heart-rate monitor/strap – speed/distance are ignored, and instead one of the other above (more accurate) methods are used.”

    So for a 405 w/ Classic Garmin HR Strap, which method is actually used for the calorie calculations?

    Thanks in advance.

    PS Great info in the article…..thanks.

  34. In your experience then, is the Garmin FR 210 more accurate than a Polar one? I used Polar for years with similar workouts. The Garmin tells me I burn maybe 60-70% of what the Polar said I burned….a little depressing but really interested in which is right.

  35. I think it depends.

    Polar pretty much pioneered heart rate algorithms, so they’ve got some really accurate stuff there. But by the same token, the Firstbeat piece is pretty solid too – for watches that have it. And if you can get a New Leaf test, that’s even better.

  36. This is so hard to figure out! Polar is good, Garmin is good. Yet the two amounts they give me are so far apart!

  37. Ok more info to see if you can give me any thoughts. I am 5’6.5, 142 lbs, 39 year old female. i have a new garmin 210 with new strap. i generally work out 4 times a week, sometimes running, sometimes at gym (elliptical, bike, weights). Today I ran 3.51 miles in 38 minutes, avg heart rate 158. Garmin says 322 calories. Seems low to me.

    yesterday I worked out at the gym on a new machine, precor cross between elliptical and stairmaster. 40 minutes, avg heart rate 130. I wore both heart straps. The garmin watch reported 308 calories. The polar strap was picked up by the machine, which reported 450 calories (I input my age and weight).

    So, with the experience on this forum, can anyone give me an idea

  38. DH61

    I have a 410, which has stopped counting calories all of a sudden.
    I have GPS off, but from your article/posts it would seem that it shouldn’t need GPS given that it has my demographic data + HR data. Admittedly, I’m not using a Garmin HRM as I was too annoyed by the quality to buy another Garmin when my old one died, but as the watch gets the HR data I wouldn’t have thought that this would matter.
    I am also running Wahoo app on my iPhone, and, as other users have posted, I think the cal estimate is higher with this than with the 410.

  39. Sarah

    I’m curious about iPhone apps. Which ones use heart rate for calorie computation when only using ANT + receiver and strap? For instance, I think Endomondo does not while Digifit does? Do you know the status of the others? Hard to find this answer on app websites. Thanks for all your hard work!

  40. I was shipped a “2010 New Premium Heart Rate Strap” from Amazon.co.uk

    Found it marginally better than the old one but still not as good as a polar strap.

  41. I would love to see calorie calculations for the Timex Run Trainer / Global Run Trainer.
    After spending some time with my TRT, I believe something is awry, either with my user settings, or with the calculations themselves, causing the watch to over-calculate calories burned by a large margin.
    If you have any insight, I would love to hear it. Thanks for all of the work you do – I love reading your site.

  42. I am getting calorie readings on my new Edge 500 that are so wildly different from those on my old Edge 705 that they make me wonder whether the calorie readings are of any use at all. As an example, today I completed a 12.13 mile bike ride in 1:23:08, and my Edge 500 said I used 465 calories. A week ago, I did substantially the same ride, in substantially the same amount of time, without either my weight or the bicycle’s differing much, and my Edge 705 said I used 1544 calories. Obviously, a calorie reading of somewhere between 465 calories and 1544 calories is of absolutely no use to me.

    And this is characteristic of the difference in results I’m getting with other rides. Initially, I thought perhaps I had my HRM adjusted badly so that it was picking up only some of my heartbeats. (This hypothesis was suggested by the fact that on my very first ride, the Garmin claimed my average heart rate was 67, which seemed improbable.) However, I now have the Garmin adjusted so that it constantly shows me current heart rate, and the rates shown seem reasonable.

    There is reference to the monitor “learning” as I go along. Will this occur even if the majority of my cardio exercise is not recorded with the Garmin? I typically bike about three days a week, which I record with the Garmin. However, the remaining days, I use cardio equipment (stationary bicycle or elliptical) at the gym, and do not use the Garmin for that. I’m just wondering whether the learning requires that the Garmin know the frequency with which I exercise, or whether it could do the learning just by monitoring my exercise several times a week.

    And is there anything else I could do to reconcile the two devices? I have a cadence meter, which I have never used; I’m not sure whether using it would help. I have set my fitness class at 9, which reflects my current level of activity. Any other ideas?

  43. Sarah

    Do you know how the Timex Run Trainer calculates calorie expenditure?

    Thanks –

  44. Anonymous

    Ray – thanks a lot for great reviews. I had a very simple question: is the Firstbeat Algorithm already installed on my 910XT and will it start collecting data automatically or do I need to buy a test from Firstbeat to then install on my 910XT?

    Thank you!


  45. FC

    Ray – thanks a lot for great reviews. I had a very simple question: is the Firstbeat Algorithm already installed on my 910XT and will it start collecting data automatically or do I need to buy a test from Firstbeat to then install on my 910XT?

    Thank you!


  46. any updates on what the newer watches use?

  47. Peter

    Hi Ray,

    Are you saying that the Firstbeat algorithms are specific to a given sport, so if I wear my FR210 running the calorie burn measurement will be more accurate than I’ll get if I wear it cycling or cross country skiing? If so, any idea how less accurate it is when using it for a sport other than that for which it was designed?

  48. Peter,

    Good question as I have just read this page and was thinking the same thing.

    However, no, I don’t think Ray is saying that the FirstBeat algorithms are specific to a sport in terms of calories, because of this:

    “Their calculation uses user inputted variables including gender, height, weight and fitness class. It then combines this data with heart rate information from the ANT+ heart rate strap. Specifically, it evaluates the time between heart beats (beat to beat) to determine estimated MET (Metabolic Equivalent), which in turn is used determine actual work expenditure.”

    If you look on the more detailed link from when when Ray quizzed Garmin, you will see that there is more detail but not much to add – i.e. when calculating calories in this very accurate way, the relative fitness of the person (stroke volume, maximum heart rate, recovery, fitness, height, weight, and whatever else they used from user inputted date, etc), can only be guessed and refined, but the heart rate that goes with it is the only other variable – not the exercise that produces the heart rate. All other research I’ve done on the internet just now, seems to suggest that this is the case. e.g. If you weight train or sprint and reach 160 bpm reducing to 130 and back up again etc for an hour, that’s the same calories as running or cycling with the same HRs – although of course that would be very hard to sustain for the hour with muscular weight training, if not impossible.

    However the reason for my post is that I hope that Ray can just confirm and answer your point, just to be 100% sure.

    Ray, thanks for excellent article and detail.

  49. JJ

    I purchased the 310XT last week but exchanged it today for the 610. Much better fit for my needs. I have a question for Mr. DCR regarding the calorie calculation. I’m a walker, not a runner. Today I took a medium walk of 3.87 miles in 58:32 with an average heart rate of 105, using the Garmin HRM (newest one). The dog slows me down. Too many things to sniff. I digress. Using the formula on livestrong.com for calculating calories burned with a known VO2max, I estimate that I should have burned 413 calories or net of 331 assuming a 2000 calorie per day need (54 year old male weighing 138 pounds). My 610 computed my calories burn to be 324, which almost exactly what my calculated net consumption is but about 20 percent lower than the gross consumption. My question is whether the Firstbeat algorithm is calculating gross or net calorie consumption. Would be interested in any feedback anyone can provide. Thanks.

  50. Bob

    Does the 610 use the 2nd generation Firstbeat Algorithm? Since the 210/410 do, I assume it does, but your article does not mention it, so I thought I’d ask.

  51. Bob

    Thanks, I am also trying to find a New Leaf test facility, but even using a 500 mile radius in the enewleaf.com locator I found nothing based on my zip code.

  52. EternalFury

    Ray, could you help in getting the attention of Garmin on the following problem, which has been lingering about for almost a year:

    link to forums.garmin.com

    Trying to contact them via Support for an update essentially sends you back to square one and you have to repeat all the evidence that has been sent to them over the past few months.

  53. Prolly

    Geat topic. Thanks!

    Tonite I ran a test between my spiffy new Garmin 500 and my older Polar 200. I actually rode my trainer with the two computers running and two HR straps on. I did a quick 38 min ride with warmup, 2 sets of intervals and a cool down. I used laps on both to delineate the HR during each period. Results: HR was pretty much spot-on identical between the two. There was only a 1 bpm difference in one of the intervals. So quite satisfied with that and was expecting as much. Calorie count however was way off even though rider data entered (age, weight, height) was the same. With an average 145 bpm over the entire work out I burnt 360 cal on the Garmin and 475 on the Polar. Quite a difference and I remain dissatisfied as to which one is best. I note here that generally the 500 reads lower during comparisons in the above comments.


  54. Damian Howard

    Hi Rainmaker,

    Could you please update the table for the latest offers from Garmin.

    Thanks Damian

  55. Thomas

    Hi ray,

    would be great if you could update this calorie device measurement table with the new Garmin devices

  56. Rajasekhar


    I am in the market to pick up a basic HRM based watch. My requirment is simple, to get estimate calorie measurement when engaged in sports like badminton, tennis and soccer( non cycling/running). I am keen on the FR70 since the calorie meaurement done on that is based on the FR60 heart rate based algorithum( right??).

    Would this serve the purpose and show me more or less a near accurate or at least dependable calorie measurement data when using it while playing badminton or soccer??

    Any help would be of great essence in selecting the right model. Thanks in Advance, looking forward to your reply sson.


  57. Tisztul_A_Visztula

    It is really a fascinating doc: link to firstbeat.fi

    But it says almost nothing about fat expenditure while there is a second by second fat expenditure % graph in Firstbeat Athlete. Having checked the manual, too, I dare say FB does not show any evidence or just hint about their estimation on fat mobilization.

    Any disagreement by anybody being more familiar with FB stuff?

  58. Joan

    Curious. I got a 305 yesterday. Has anyone compared results from New Leaf testing to those at this online site? link to shapesense.com

    I doubt I’ll ever have access to a testing center. Thought estimates were better than none at all in that field. Range of 37-41 ml/kg/min for two of the tests so far (the walking test I guessed based on experience just to see what it would throw up. Close range to the first age and weight score. I picked a number in the middle to go with for now until I can test. Cool alternative, if it’s anywhere close. Can anyone confirm? Thanks!

  59. mjervis

    Have Garmin ever updated the firmware on the Edge 705 since this post? Or is it still doing the poor man’s calorie calculations?

  60. Josh

    Absurd that the power meter is listed as the “least accurate” when it is the most accurate, since it is the only device actually measuring energy output in real time rather than estimating it.

    • DC Rainmaker

      Nice effort on the bolding. Unfortunately, you’re wrong.

      It’s only measuring the output, not YOUR effort into it – thus not the actual caloric burn (after all, this post is about calories). It’s due to this that it doesn’t account for your inefficiencies as a cyclist. There’s a good post on this here: link to bikeradar.com

      As a further example, if you took two equal weight riders/bikes – one a TdF cycling pro, and then an overweight 5’2″ woman that does no fitness activities, and had them both ride at 175w, the girl would burn significantly more calories than the guy, who wouldn’t burn much of anything. This being the result of efficiency.

    • Josh

      Sorry, DC, but linking to a forum is not a “good post”. It’s about as far from credible information as you can get.

      The fact is, only the power meter is directly measuring work done. All those other methods are faking it via estimation algorithms. Algorithms that are skewed horrendously by everything from weather to fatigue status. They’re as reliable as a Garmin Vector release schedule.

      Whereas measurements for mechanical efficiency are extremely well known and consistent – in essence, gross mechanical efficiency is almost always 20.5% ±1.5%. I went looking for papers that support that figure. Heck, I quickly found so many I went looking for a counterexample instead. There is one: the top handful of gifted and hardworking cyclists improve on that gross efficiency range, getting up to 24% (we don’t count Lance’s 25%) [1]; for all intents and purposes, they are outliers and not a useful data point; moreover, this efficiency level is not retained[2].

      So, if a club cyclist rides at 175W for an hour, they should consider themselves to have burned 735 kcal, ±1.5%. For the world’s top-10 professionals, a little over 600kcal.

      And, ahem, far from being “not much of anything”, that’s at least 25% of your myological glycogen storage and failure to account for it could be the difference between hitting the wall or not.

      Similarly, I don’t see why bringing an untrained athlete into the discussion adds anything useful. “Let’s go find someone who doesn’t know what they’re doing and therefore wastes lots of energy”. Uh-huh.

      In summary, if you really want to measure kcal, don’t use HR. Use a power meter, a device that is actually measuring physical energies and just use avg power (W) * time (h) * 4.2 kcal/W/hr.

      [1] Int J Sports Physiol Perform. 2012 Sep;7(3):200-9. The Tour de France: an updated physiological review. Santalla A, Earnest CP, Marroyo JA, Lucia A.
      [2] IJSPP. 2012, 7, 397-400. The Cycling Physiology of Miguel Indurain 14 Years After Retirement. Mujika, I.

    • Thanks DC, this corresponds with the general principle that as you do an activity more, you get more efficient at it, and therefore burn more calories–and would also explain why I would get such different calorie estimates from runs where I wear the HR monitor or don’t. Over the 15 years I’ve been running, my weight has stayed about the same, but of course after 10,000+ miles I’m way more efficient, so without my HR monitor for an easy, flat run it says the standard figure of ~100 cal/hr, vs. with it it’s more like 75.

  61. Simon

    Many thanks for this research and publication – I was trying to find out why my Garmin 405 gave me 2,700 calories for a two hour ride. I’ve now found I can switch it between Running Mode and Cycling Mode, and also now know why the calorie count was twice what it should have been.

    Very interesting stuff – well done!

  62. Jae

    Good stuff here, I was just directed here by Garmin support and this thoroughly answered my question. I did a 13.5 hour hike up and over Mt. Madison, Adams and Jefferson and my Garmin 405 said i only burned 630 calories. No, the heck I didn’t!! haha So I wrote in wondering what was the technical reason this occurred. Especially since I run at least twice a week and produce caloric stats that make more sense. After some explanation they sent me here. This is exactly the nitty gritty details I was looking for. I think I’ll be investing in new Garmin that will measure my heart rate not based on my distance, weight, speed, etc but of my actual heart rate data. Thanks again!

  63. Jae

    I have a question. Is the Garmin Forerunner 610 also good for non-running activities, like a workout in the gym to track time, max HR, avg HR and calories?

    • Yup, it tracks calories without any issues there. It supports the Firstbeat 2nd gen.

    • ChaimN

      I just got the FR620 and used (short tests of 15 min each) it together with my old FR410 (one HR monitor / 2 watches). I got huge diference in the Calories calculated between the two; FR620 = 90cal vs. FR410 = 140cal. I conducted the test after I got a reading of 300cal in a spinning class vs. a 600cal reading on the FR410 for the last 4 years. Any ideas for what is going on? Garmin could not help me…

  64. Jae

    perfect, thank you for the quick response!

  65. Richard

    Hi Okay For the last 2 years I’ve been using a the Motoactv to log my runs, but I’ve just got a Garmin Forerunner 310xt, and there is a huge difference in the amount of calories burnt. Just some background:
    I’m 50 years old exercise 5 or 6 times a week on average (mainly running), I’m 175cm tall and weigh 69kg. On the Garmin device I set my activity level to 7 on Garmin Connect, and I also enabled the “life time athlete option as my resting heart rate is below 60 (49 actually). My max heart rate is 187 recorded on a recent race. According to the Garmin after a 10km run at a pace of 5:34 per km I only used 185 calories, which seems ridiculous. A similar run on the Motoactv says 678 calories. 185 seems impossible I’m sure I’ve used more than that typing this comment. Any ideas what’s going on?

  66. Duncan

    Does the 810 factor in air temperature at all when calculating calorie burn using speed / distance only? Reason i ask is i did the same ride 2 days apart and got the following results:-

    Ride 1 – 30.76km / 59m 25s / avg temp 28.1c / Calories 1157

    Ride 2 – 30.76km / 58m 14s / avg temp 32.7c / Calories 1893

    Seems like a massive difference, considering there was only a 0.6kph difference in average speed, although average temperature was 4.6c higher on the second ride…

  67. brianh

    Great article, as always! I do have the same question as mjervis though: “Have Garmin ever updated the firmware on the Edge 705 since this post? Or is it still doing the poor man’s calorie calculations?”

  68. Mike M

    Thanks to all for great information, but now a question:
    I’m using the Wahoo WFHR3 Heart Rate strap with a Garmin Edge 500. Anyone know if this device is OK for the calorie calculation? It seems to work fine insofar as reporting heart rate, but the Garmin reports about half the calories compared to other formulas(straight distance: Distance*Weight*.28 or Power: Avg power*4*time) Example today: 4 hours ride time, 69 miles, 5000 ft of climbing, Garmin reports 1272 calories. My profile is Male, 58 years old, 125 lbs, activity level 8.

    • Hmm, the only thing I can think of is if the Wahoo strap isn’t sending over HR RR information, perhaps Garmin is using that in part in the calorie calculations – which could be causing some missing information.

  69. Mike M

    Thanks Ray

    That was a consideration of mine after reading your info and all the posts.

    I might just try a Garmin HR Strap.

    Thanks so much for all the info that can’t be found anywhere else!

  70. Richard

    If you ask me Garmin are using pure “Guessology” in their calorie calculations. Here are two examples using the 310xt :
    Distance: 25.01 km Time: 2:24:09 Avg Pace 5:46 min/km Elevation Gain: 277 m Calories: 555
    link to connect.garmin.com

    Distance: 7.01 km Time: 38:37 Avg Pace: 5:30 min/km Elevation Gain: 67 m Calories: 508 C
    link to connect.garmin.com

    According to which I ran for about 1hour 45mins longer and 18km further in the first run, which was up a mountain while the second was on the flat , but I only used an extra 47 calories! I just as well pick the calorie count out of a hat.

  71. Charles

    I have a similar experiences to Duncan. Same ride, distance, time, etc and do wear a HR monitor. Calorie calculation on 810 is not only inconsistent but much lower than the 910. Love the products for the most part but very disappointed in this regard. I wish they were accurate and consistent.

    • In theory those two products should be using the same v2 variant of Firstbeat for their calorie calculations. Have you double-checked that the following settings are identical: Age, Athlete Level, Weight?

      I don’t think weight is used in it, but just in case.

  72. Charles

    All settings are the same

  73. Don

    How can I find the actual algorithms, even if only the speed/distance one? My googling has so far not found a hit.

  74. Christopher Rupert

    I never knew about this great device, thanks for the information. But, which one will provide the actual result, this tool or the online tools… that most runners would use, I really wonder! Presently, I trust the link to calorie calculator provided on the Runnersworld.com website. I found it quite accurate and helpful.

  75. Steve Knapp

    Do you know how “fitness class” influences the algorithms?

  76. Thomas Moiln

    Hi interesting reading!
    The new Garmin FR620 (FR220) how accurate do you think it will measure?
    There is some VO2 measurement in the FR620, how accurate is that?
    BTW i have ordered a FR620…

    • It’ll largely mirror the above, as it uses the same underlying Firstbeat technology. But I’ll cover it a bit more in my review as well, comparing it to past units worn at the same time.

    • Eli

      Firstbeat Athlete (i.e. the same algorithms) isn’t used to test for VO2max, you have to actually set that as one of the properties of your profile if you want to improve its accuracy along with setting your vital capacity. (I believe without setting your vital capacity is guesses based on your height)

      Does the 620 let you set those two values to make the algorithm more accurate?

  77. I’ve been using my 620 to determine calorie counts for other activities, like tennis. I calculated that I burn an average of 350 calories per hour playing tennis, which is decent considering I usually play for 2-3 hours. But what I’m unclear on is whether or not it includes calories I would’ve “burned” watching TV on the couch. If so, it doesn’t seem fair to track them against the calories I consume.

    Have any idea?

    • Andrew

      Your garmin unit will account for your standard metabolic burn rate, as well as your burn attributed to the activity you are doing. so you would be double counting the burn if you have a base rate of say 2000 calories a day and then add your 350cal/hr on top of that.
      Best way to do it would be calculate your hourly BMR of calorie burn and subtract that from your activity total.
      ex. 2000 daily BMR calorie burn = ~84cal/hr
      If you play tennis for an hour = 350cal
      Total calorie burn attributed to the activity = 350-84 = 266cal of incremental calories burned.

  78. Lisa

    How can I use VO2max info I already have? I’ve done a max GXT test in the labs in my department so I already know my info. Is there any way to just input that information to my profile and have it use that?

  79. Liv-Berit

    I’ve read your post, but I’ve still a question about how accurate the calorie calculation on my Forerunner 210 is. Yesterday I went for a 50 min walk, had an average HR of 140, walked 4,39 km at an average 5 km/h. The Forerunner says I burnt 264 calories. However several other calculators (f.ex Endomondo) says about 600 calories.
    Reviewing my outdoor walking sessions the last month the Forerunner 210 shows an average of 219 calories less then the Endomondo. Why?
    I have the same problem indoors at the gym. The crosstrainer or treadmill shows 300-400 calories (depending on the time and intensity), but the Forerunner 210 shows about 130-140 calories. What can I do to improve the accuracy? It is not possible to choose an activity level on the device, other than yes or no to athlete. I’ve read that activitylevel and VO2 Max are important variables in the Firstbeat algorithm. But those variables Are not possible to register in the device.

    The inaccuracy is a major problem to me, and I’m very dissatisfied about it. Considering to buy another watch. Do you know of other watches (budget-mid range) that have a greater level of accuracy? With or without GPS included.

    Grateful for any help! This is really frustrating!

    • There’s a lot of factors that drive calorie burn. However, I think the other devices are actually liking overestimating calories. The general ‘golden rule’ of walking/running is 100 calories per mile. Thus, at roughly at about 2.7 miles it burned 264 calories is quite reasonable. Endomondo saying 600 calories is simply crazy.

      There are cases where calorie burn is higher (for example, if you weighed significantly more – for those that are significantly overweight), or, in cases where you’re at/near VO2Max intensities.

      But honestly, looking at the examples you’ve given, the Garmin numbers are reasonable, and the other one isn’t (without knowing the treadmill distances, it’s hard to say there).

  80. Liv-Berit

    Thanks for quick response! The point is that the calorie calculation of the Forerunner doesn’t seems to tale my weight into account. I am 120 kg, thus the caloroes burnt should be higher than for a normal weighing person at the same distance.
    Another strange ting is that the Forerunner calculates that I burn approximately the same amount of calories walking half the distance at half the pace and double the time. Is that likely correct?

    • Ahh, gotchya.

      Strange. I don’t know enough about the scientific side to know whether (for example a 60kg person burns half as much as a 120kg person). In general, I’d believe data from Garmin, Polar, etc… over data from Endomondo – only because I know where that data comes from (FirstBeat and a few other Finland firms focused 100% on HR calorie burn). Of course, whether or not the unit has a bug that doesn’t account for weight is potentially valid.

      If you’re wearing a HR strap, it would be using those tables to determine it, but again, it does seem odd it’s not being biased a little bit on weight.

  81. Tim

    Hello Rainmaker,

    I have a FR 305. I have been attempting to work out my calories burnt in a standard weights session.

    I disable the GPS in the gym, and the result is that 0 calories are burnt, despite an average HR of 120 across a 45 minute session.

    Do I need to change settings to calculate calories off the HR?



    • That’s odd. Are you on the latest firmware? And have you set up your user profile (age/weight/etc…)?

    • Silvio Glöckner

      Hi, I too have the FR 305. In my experience it only calculates calories if it has speed data. So if you train indoors you either have to use a footpod for running or a speed sensor for your bike.

  82. Ryan Cohlhepp

    Any updates since you wrote this?

    • Generally speaking, everything is actually pretty correct still. All the new devices utilize the Firstbeat v2 algorithm, but beyond that, basically the same.

      That said, it’s on my list to work with them this spring on getting it fully refreshed.

    • Emily Q

      I would like to see Garmin alllow is us to input the new leaf info on the newer edge. For now I keep my 800. Could you address this with Garmin?

  83. Eduardo

    Hi Ray,
    I have a RC3GPS Polar and Garmin Edge 810 + Vivofit.
    In the gym I use the session and the RC3GPS vivofit both with HRM Straps.
    In both sites (garminconnect and Polarpersonaltrainer) have the same value for average HR and HR MAX, but calories are more in the Polar vs. 311 Kcal 445kcal (vivofit)
    Do you know why this happen?
    Both devices should not have the same value?
    Which device is more acurate?


    • Eduardo

      Sorry bad english in my previous post

      Hi Ray,
      I have a RC3GPS Polar and Garmin Edge 810 + Vivofit.
      In the same gym session I use the and the RC3GPS vivofit both with HRM Straps.
      In both sites (garminconnect and Polarpersonaltrainer) have the same value for average HR and HR MAX, but calories are more in the Polar vs. 311 Kcal 445kcal (vivofit)
      Do you know why this happen?
      Both devices should not have the same value?
      Which device is more acurate?


  84. Esther

    I have a Forerunner 610 and the soft strap Garmin HRM. When I wear the HRM, my average calorie burn per mile while running is at least 10 BPM lower than when I don’t wear the HRM (as per Garmin Connect’s data when I upload). Both the watch and the website have my correct age and weight in the profile data. And yes, I’m comparing runs of similar length and intensity, similar terrain too. So which is the “correct” data? Thanks.

    • Honestly, you’ll never really know.

      Calorie data is a very imperfect thing. Everyone (device/algorithm/etc…) claims they are right, but it’s very difficult to apply an algorithm to the entire world’s population for any activity you do. It just doesn’t work out.

      I wish I had a better answer there. From a pure math standpoint, the one with the HR monitor is likely more accurate, since it’s evaluating your work effort, versus the other is just doing simple math of weight & distance.

  85. Isaiah

    Hey Ray,

    I started using a HRM a few months ago, and for a long time I was getting really bad spiking issues (heart rates above 250, average heart rates in the 180s). I’ve now mostly solved those issues, but I was wondering whether those might factor into my “athlete profile” and affect my calorie results now. If so, is there an easy way to reset the athlete profile?


  86. Cary


    I have the 220. I recently had a V02 Max test which calculated my calorie burn (and fat and carb metabolism) along my heart rate profile. Using those numbers to calculate my caloric burn (based upon average heart rate for an entire run) I come up with caloric numbers that are way different than what my 220 is calculating. Example: I just ran a hilly (6800ft of gain) 50k trail race on Saturday in 4:30:30. Average HR was 137. Based upon lab data I burn 951 calories per hour at a hear rate of 137. Thus, I get 4,275 calories for the total. My 220 says 3,015. I should note that I have a somewhat low Max heart rate of 165 for a 45 year old trained athlete. I weigh 155 and am 5’10”. I put whatever data I could into my Garmin profile. Any ideas on how to get the 220 more accurate? Or could the V02 Max data be overestimating caloric burn?

  87. JakiChan

    Since Garmin updated the 310XT to the second gen of the Firstbeat technology I’d love to see them do the same to the Edge 500. (I’m sure the 510 has it, but it’s probably not worth it.)

  88. pkiszk

    I came across this article while pondering about SportTracks (3.xx) calories calc methods. I use ST to record my running, rowing (concept2 rower) and cycling (no power meter though). I use HR strap all the time. Concept2 rower gives me detailed power data as well. Now, ST allows you to determine calories spent on the basis of HR (settings under categories). Does this method use Firstbeat (1 / 2?) – under their “Heart rate method” setting ? This would be great and solve any issues for me at least (a heavy ST user). If not – what method ?

    I must also say, that Old Man’s Biking plugin (GPS2PowerTrack) adds Power based calories calculation which gives you a bit different calcs amounts (a few % lower) but by not a big amount (for my workouts on a rower). Which, assuming that what Josh said about that particular method is accurate, suggests ST’s method relying on HR is also quite good.

    Having said all of that, I still doubt if a 30min moderate run (5km, so pace of 10km/h, avg 70% max HR in my case) yields in 330 in calories burnt (or 660 per hour) – I remember a rule of thumb for running – that it burns 300-400 calories per hour (or, to say figuratively, one needs to run for an hour to burn a donut cake).

    So how come the method based on HR reports 50% more than that (or more than 50% if one assumes 300cals as basis) ?

    On the other hand, it matches the golden rule of 100calories / mile (5km is 3.125 miles). All I want to say – is that I remain skeptical about calories burnt as reported by ST / Firstbeat method vs calories intake that we consume in food. I think one needs to adjust downwards the amount reported by ST or Garmin in order to keep the intake/output calorie balance in our daily life. I would welcome your views.

    [But I would love to be wrong and find out that a moderate off road cycling at an avg of 65% max HR for 2,5 hours burns 1500cals, as reported by ST in my case – but I simply can’t believe it !]

  89. dgpete

    Hi Ray,
    Wonderful article like all the rest!
    Like many amateurs, I would LOVE to have a power meter but I have four kids, one still in college so that will have to wait. And while I know very well that calorie calculations can vary widely and are often very inaccurate it is still just one more small piece of data to preuse! Unfortunately I’m a data geek with insufficient funds for a PM;-)
    So along those lines, while I know it’s an old thread, I can’t seem to find any more recent info anywhere as to whether the newer Edge 810 and 1000 use the same methods/metrics to calculate calories as the tables you have above.
    I’m also interested in what order the Garmin devices will use them.
    Do you know or can you point to an info source?
    Anyway, keep up the great site! I will always purchase using your Amazon link if I can!

  90. Juro

    Hi Ray,

    I have recently switched from one HR strap to another; I was using the 4iiii strap and now I have the Scosche Rhythm+. I am still using my Garmin fenix.

    What I noticed is that while both straps give me the same average and max HR readouts, the calories calculated by the fenix for a run that I run often differ significantly (I am talking ~800 with the 4iiii strap and ~1000 with the Scosche).

    What role does the HR strap play in calculating calories? I thought the strap merely transmits the “beats” to the head unit which does all the calc; meaning same HR profile should result in very similar calorie burn.

    • A huge role. It’s one of the biggest challenges with optical HR, is that it can’t correctly do heart rate variability (HRV/RR). It guesstimates it. For some people, it ends up pretty close. Yet for others, it’s all over the map. And yet again, some people it’s really close on some runs and way out of whack on others.

      Right now it’s a limitation of the optical technology across the board. The Scosche sends out a best guess, but…it’s still a guess.

    • Juro

      Ah, thanks a lot… so that means HRV/RR is transmitted for all EKG-based HR straps? I somehow thought that’s a feature of the “premium” straps only.

    • Yup, correct. In fact, on ANT+, it’s required as part of the ANT+ specification. So, every strap has to send it. Which, is ironically why the Scosche sends it…because the spec requires them to send something. So they basically take a swag at it (as they are required to fill in that data).

    • Juro

      Thanks. That’s disappointing, I was expecting that I will be sacrificing only the recovery and training intensity metrics (which fenix does not support anyway) by moving to Scosche – did not expect the calorie count issue… (Context: historically I believe my fenix gave me very accurate calorie counts – lower than what non-HR methods used to produce, inline with the increase of fitness I have managed to make happen this year.)

      You are right it’s a bit random, too, apparently Scosche’s dummy HRV is closer to an average run pattern.

  91. Kevin Hudson

    Ray, was wondering if you could help explain this. I’ve been running with a forerunner 205 for years. Finally decided to dip my toes into tris, and being a tech guy I splurged on the recent sales for the garmin 910xt and the mio link. My first two runs with my Mio Link Heart Monitor were 2-3 miles and showed about 120 calories per mile and a training effect of 3.3. Seemed about right.

    Then my recent two runs were 4-5 miles and the calories plummeted 70-75 calories in a mile and the training effect is going to 5 quickly. Then yesterday I did 6 mile run and it calculated the calories at a little less than 100 calories per mile. All runs the same pace. I’m can’t figure out why the calories burned dropped but it seems almost impossible that I’m running only at 70-90 some calories per mile. Any ideas? Granted because of my recent schedule these first two weeks of owning them I haven’t gotten any long runs in, so that may be affecting the training effect. Any help would be greatly appreciated!

    • Yup, unfortunately it’s a limitation of the optical HR sensor. It can’t do HRV (heart rate variability) well, so it just estimates it. Sometimes this works out, and yet other times it’s all over the map. This impacts calories, recovery time, VO2Max, and training effect (on Garmin and non-Garmin devices alike).

      I’ve been meaning to write a longer post on the topic…

    • Kevin Hudson

      That’s what I was afraid of. I was hoping I was doing something wrong. Thanks for the reply.

    • Forrest

      If you ever do find the time to do a post on this, a lot of your adoring fans would love it.

  92. Michelle

    Classic strap gives me about 130 to 140 calories burned per mile, while the newest strap (came with FR 610) clocked in first around 88 and then today at 110. I’m an average sized gal so I’m guessing the new hrm is more accurate.

  93. Hi Ray,

    Is there something I can do with my FR920xt ro get an accurate calories burned? Like manually input on the profile setting or something?

  94. jkoch

    Does anyone know which algorithm the Edge 510 uses?

  95. Brandt Hambrick

    Do you happen to know how Garmin is calculating HR when it gets imported data from another app? I’m syncing TrainerRoad data (using Tapiriik) and a hour ride at about 15 MPH says 571 kJ, but Garmin calculated it at only 136 Cal.

    I connect my Garmin HRM and Cadence Meter using ANT+ to my pc, riding on a Kurt Kinetic if any of that matters. I did not have any watch or bike computer in the mix.

  96. Terrance

    I added some runs in Garmin Connect manually instead of having my watch do it automatically and the calories it calculates (I can change the field if I want) were different from what it would have estimated if I uploaded via watch. Any idea why that would be? My guess is because Connect makes the estimation in one case and the watch makes the estimation in the other?


    • Indeed, totally different methods. For online, it’s basically a simple weight/distance calculation (very basic), whereas in the device itself it takes into account the different methods outlined above.

  97. John Vance

    What is “fitness class” anyway, and how is it used in calculating calories used? When I enter fitness class in my Garmin, it only wants to know how many hours a week I exercise. I fail to see how this translates to chemical energy expended to produce work. Two people can be the same weight and ride similar hours, but one could produce double the power, and therefore expend double the calories, at FTP.

    I weigh 130 lbs. My Edge 500 calculated 1600 kcal for an 81 mile ride with 3,000 feet of climbing at an average pace of 19 mph. Using my average power for the ride of about 160 watts, i get 2450 kcal. I know from logging food and exercise over the past year that if i used the Firstbeat number of 1600 kcal, i would start losing weight at about a pound a week, which is the last thing I need to do.

    For me at least, the Firstbeat numbers are laughably off.

  98. Harith Al Kubaisy

    I have a FR620 that I sometimes use when playing football (soccer),

    This week I played twice in the same field, with approximately the same effort and time, but the calorie burn estimates given by the Garmin watch and my Polar FT-7 are way off:

    -Duration: 1:02:43
    -Average HR: 166
    -Max HR: 194
    -Calories burned: 1079

    -Duration: 1:04:59
    -Average HR: 165
    -Max HR: 193
    -Calories burned: 753

    I’ve been always getting higher calorie burn estimates when using the Polar FT-7

    What do you think?

    • Harith Al Kubaisy

      I forgot to mention that the readings on the 4th of Feb are by the Polar FT-7, where as the 11.02.2015 data are by the Garmin FR620 with the HRM Run heart strap

    • Calorie burn between manufs is really tough. Everyone claims that they’ve got it right (and all have really smart dudes doing the calcs. In fact, all the companies that do these HR calcs are within about a 10-minute drive of each other in Helsinki (+ Polar up a bit further north in Finland). They all kinda rotate between each others companies over time.

    • Harith Al Kubaisy

      Thank you for your quick response. I would understand a discrepancy of +- 50 calories, but 300 calories is just way too much.

      I always had higher calorie burn estimates with the Polar than the Garmin, which really makes me curious which one is more accurate.

      Have you tried to test the accuracy of this metric before?

    • Mike W

      Perhaps Garmin doesn’t include your basal metabolic rate — that might account for 1/3 of the difference between the two.

      Personally I’m ok with what Garmin reports from my FR620 recorded workouts.

  99. Przemek


    what is your age, weight, resting HR and max HR ? Also, your VO2Max, if you have it. I could try help you pick the one that is closer to your burn rate on my home-brewed calculations.

    • Harith Al Kubaisy

      Hello there, thank you for your concern.

      I’m almost 24 years old, weigh 75 kilograms, and have a resting HR that is around 56-58 last time I checked. I haven’t done an actual Max HR test, but been using formulas that put it in the ~185 range.

      My VO2Max from my Garmin watch comes out to be in the range of 40-45.

      I know I’m not very precise, but then again, I’ve been working out for a couple of years only.

      Thank you again!

  100. Przemek

    Your HRM is clearly above 185 ! Depending on the intensity of your soccer game, I would say your max is 200 or above 200. If you want to check this, you need to test this in proper conditions, racing is best – assuming you have a discipline in which you are technically efficient. Could be running, cycling, rowing. Any activity involving large muscle groups.

    When it comes to the calories burn. I use FR 620, Edge 810 and FR 910xt. Used to use FR 310xt and Edge 800. Edge 810 is the most conservative (reports lowest values), then 310xt, then FR 620, then 910xt. Having seen my VO2 consumption data at various HR percentage wise, I used the Weir formula to estimate caloric burn (assuming it is accurate at other than BMR level, I do not know it yet). I weight 74-75, so about your range, but I am 38. On the other hand, my VO2Max seems high (63ml/kg), which can be attributed to poor equipment calibration (Cosmed mentioned above) or, it could be real. I can’t tell, plan to repeat it later this year with another provider.

    To make this short – assuming your max HR is around 200, average of 166 bpm is somewhere around 83% HRM. My burn rate at 83% HRM is around 820-850 kCals, including BMR (take 50-60 kCals for that), according to Weir formula. Having looked at FR620 caloric burn over the last couple of weeks I think it is pretty consistent with my caloric burn estimated by Weir formula (but not VO2Max data which suggest it is as high as 1000kCal / h). So I would rely on FR 620 in your case, too, but not Polar.

    Also, I log calories eaten each day – and I used to log Edge 810 caloric burn (around 12-15% lower than FR 620) and should FR620/Edge 810 data be materially wrong (30% would be material – your difference between Polar and FR620), I would be losing weight. But I keep it. So FR 620/Edge 810 is roughly allright. I am planning to run some regression analysis of my data, but lack time to do this. Still, I think there are too many variables to be able to nail it really down and it is better to spend time elsewhere. Garmin got it pretty close to what we need.

    If someone wants more info, pls post here, I will try to contribute if I can.

    • Harith Al Kubaisy

      First of all, I want to really thank you for your time and effort. I really appreciate it.

      Regarding my Max HR, I only used the number 185 which is what comes out from the formulas. In my last 10K race (30.01.2015) my Max HR was 190, and it is important to mention that I was running at slower pace because it was my first race after 4 months battling ITBS.

      Max HR in half marathon last year was 185 (but that was using Polar FT-7)

      Do you think I should set my Max HR to 200 in the settings?

  101. Przemek


    the best way to establish HRM is to go all out during a proper test. There are a lot of protocols to do this. For now, I would use a 200 HRM, you can get as high as 194 during soccer, you must be able to go above that in all-max effort. The question is this – what do you want to use it for – to improve the calories calculation in your watch – that may have no effect. If you want to establish your training zones – this is important, but that is not everything. Your lactate threshold is key. Again, you need to do some testing. In my case, my home-made tests proved to be pretty consistent with what the VO2Max test reported. If you want, I can give you details, if you can’t find them online.

    • Harith Al Kubaisy

      Yes, and I did reach 202-203 playing soccer before, so I get your point.

      I know it won’t improve calorie burn calculation but I want to incorporate HR zone training this year and I felt that my zones were off.

      Regarding your details, I’d be interested as I’m a statistics lover.

  102. Przemek

    In order to determine your HR at Lactate Threshold you should do a 30min test, and take the average HR of the ending 20min HR. It is easier to do it indoor – cycling for example. Or rowing. Have look here:

    link to cyclingtips.com.au

    or here:

    link to beginnertriathlete.com

    In my case it was around 87% HRM and the VO2Max test put it at 88% HRM.

    • Harith Al Kubaisy

      Do you think a normal stationary home exercise bike will do the trick for the test?

    • przemek

      if it has variable resistance level that can make your cycling hard, then yes.

    • Mariusz

      Zaczynam zabawe z bieganiem …chcialbym powoli trenowac na triathlon .
      Wydajesz sie osoba z duza wiedza ….z ktorej chcialbym skorzystac aby ulozyc trening.

  103. Dave Le Fevre

    Last summer I’d noticed that my Garmin Edge 1000 gave much lower calorie figures if I wore the pulse-rate strap. So I’d performed an experiment by doing the same ride with and without the pulse-rate strap.
    With the pulse-rate strap – 1:46:19, 25.7 miles, average 14.50mph, max 31.54mph, average cadence 67, max cadence 101, average pulse 121, max pulse 161, calories 567
    Without the pulse-rate strap – 1:45:27, 25.76 miles, average 14.57mph, max 30.35mph, average cadence 68, max cadence 109, calories 1163
    So factoring in the pulse-rate reduced the calorie estimate by a factor of 2.05! At the time, I found that surprising.

    My cycling pulse-rate reaches relatively high figures (for my age), so I’d have assumed that, if anything, the with-pulse calorie figure would be higher than the without-pulse figure.

    I then repeated the experiment omitting also the cadence sensor. That made no significant difference. (I hadn’t expected it to make a difference, but it was worth trying.)

  104. Przemek

    Your calories, with HR strap on, look indeed low, but I would still rely on the low figure calculated on the basis of your HR rather than without it. I suspect you must be pretty thin/small and/or with a high HRMax. Also, did you enter your weight, age, max HR and resting HR into your Garmin ? This is crucial.

    PS. I would burn around 900-950 kCals for a similar type of workout (based on your avg HR and speed info alone).

  105. Dave Le Fevre

    I’m not really that concerned by the calorie figure per se – I only performed the experiment to quantify what difference (if any) the pulse-rate strap made.

    “I suspect you must be pretty thin/small and/or with a high HRMax”
    My mass is a bit under 62kg. My BMI is usually between 20.2 and 20.5.

    My maximum pulse-rate is low, but is high for my age. I’m 68, so I’d anticipate a maximum of 220-68=152, yet I register about 15 more than that on steep climbs.

    “did you enter your weight, age, max HR and resting HR into your Garmin”
    Weight and age, yes. HR figures, no. I intended to when I first configured it, but I have never yet found where to enter them.

    I noticed that if I observed the HR %Max datum and did the sums, it assumed that 100% was 152. So I assumed that it did its own calculation of the maximum, and had no way of defining the resting rate.

    “I would burn around 900-950 kCals for a similar type of workout”
    It’s a hilly route, I wasn’t going that fast, but I’m not nearly as fast as some decades ago. So it’s not easy to compare. Though perhaps calories burned is simply a function of route, speed, mass, and is unconnected with age or how hard one finds the ride.

  106. Przemek

    Without proper input of these parameters into your Edge, the calories burnt data is meaningless.

  107. Dave Le Fevre

    Well, such data ought to be under User Profile. But they aren’t. So I’d assumed that they weren’t configurable.

    So now I’ve hunted further, and I found them under Training Zones. Thanks.

    But as far as I’m concerned, the calorie datum is useless. There’s nothing that I do as a result of that datum – I don’t eat more or less. And I don’t trust that datum to be accurate.

    My sole purpose in posting here was to highlight the huge difference between the calorie data with/without the pulse-rate strap. However, by posting here I’ve learned something – that my Garmin had somewhere a place for me to define my maximum/minimum pulse-rates. Thanks again for that.

    As an aside, considering the huge range of displayable data, it’s surprising that highest pulse-rate reached isn’t one of them. It’s displayed in the ride summary, but I cannot find it as a displayable field during the ride. A surprising omission.

  108. Przemek

    This is the calories measurements blog post, so I discuss it too. Once you enter your data, Edge computer should do a pretty accurate job when it comes to calories burnt estimates – assuming you wear your HR belt. In the absence of it, these are rather rough estimates based on distance and time covered and they tend to be on the high side.

  109. Mark

    Hi Ray,
    Great site, and good info all round.. Some time ago after your 910 review I purchased one of those… and recently, having ready your Edge 510, review detailing Live Tracking, my wife bought me a 510, as she feared I would fall off my mountain bike in a ditch and she would have no idea where I was…( I tend to be a tad accident prone)

    But am now confused.

    If I do a 20 mile Mountain bike ride, my 910 Garmin, tells me I burnt 2,200 Calories, while the Edge510 tells me 1,600 Calories.
    I read your article on how the different devices calculate calories, and I get it about the different brands, and different methods… with strap and without.
    I understood, as I have no Leaf VO2 profile, both devices would use the firstbeat calculation method.
    Given BOTH devices are Garmin, both share the same Garmin Connect account, with same profile, same Weight, Sex Height. And both are reading data from the same HRM sensor on my chest… shouldn’t I expect to get the same reading ????

    What causes the difference?

    I have read a couple of forums suggesting the EDGE does read very low, and that there is a bug on the Edge510 WHEN used with a HRM strap. But most of these compare against Sumit or Polar… The Edge510, has the 3.4 firmware you also detailed…
    Any wisdom would ease my confused brow.


  110. Dave Le Fevre

    Now that my Garmin Edge 1000 knows my peak pulse-rate (thanks Przemek!), I repeated my experiment of August 2014.

    1:41:16, 25.52, average 15.12mph, max 35.34mph, calories 574

    Going about 4% faster than before, I consumed about 1% more calories than before. So it looks as if the Garmin knowing my peak pulse-rate doesn’t cause it to alter its calorie calculations significantly.

    By the way, if it should find that a user exceeds what it believes to be their peak pulse-rate, it could simply update its stored peak pulse-rate (and inform the user at the end of the ride). That would seem (to me) to be an obvious thing to do.

  111. james ginn

    One burns 90 to 120 calories per mile period depending largely on your weight. Its simply force through a distance. But Garmin is not even close. So why can’t Garmin get this right.

  112. Jeremy

    I just got a Vivoactive and I’m noticing a huge difference with walking and calories, activity vs just steps. (This is not including an HR monitor.) I walked 18k steps the other day, about 9 miles, and it showed that i exerted 109 calories from that. If I did all that as an activity, choosing the walking activity, i’m sure that the calorie count would be like 500 or so. Because that’s several hours of walking. Shouldn’t they be the same thing? Or at least close?

    Isn’t that a huge discrepancy for two ways of recording the same activity? I guess the walking activity is good for tracking the route with GPS, but I would think the calorie algorithms should come out not orders of magnitude off from one another.

    Anyone know what’s going on here? Please tell me if I’m looking at this incorrectly.

    • Yeah, 9 miles would definitely get you more than 109 calories (rough math is 100cal a mile). Something is definitely up. I’d reset things and see if that helps, or contact Garmin support. :(

  113. Przemek

    Walking is overrated. It burns close to nothing over our normal burn rate (BMR). So 109 kcal is low but so what. If you want to burn calories get your heart rate into 65% of your HR Max or higher. Walking does nothing of that kind. No matter how long. What do you want to achieve with obtaining the calories burnt – lose weight ? Change eating habits first of all. Simple stuff does the trick, no junk food, moderately sized meals, less fats and simple sugars (that includes fruit), more greens and vegetables.

  114. Marsha

    Thank you for all the great intel! Do you know what makes the total calorie number in the Active Calorie Report different from the active calorie number in the Total Calorie Report. The help desk couldn’t address.

  115. Sally

    Hi, I would like to enquiry whether the Garmin Fenix 3 is able to calculate calories without the hrm? Thanks

  116. Frank Bertelsen

    I am having an issue with my Garmin Edge Touring Plus device, and I would like to know if the way it calculates calories is correct, as I have not seen any formulas that work in a similar way. I am using an ANT+ heart rate monitor.

    What it does is that it lowers the calories burned for a given heart rate depending on the time/distance I have ridden.

    Example: When I turn on the device, it says that I burn 10 calories per minute at a heart rate of 127 bpm. After 40 minutes I need a heart rate of 133 to burn 10 calories per minute, and after two hours it is up to 145 bpm.

    I can easily burn 600 calories during the first hour by riding a normal pace, but after 4 hours it is impossible for me to burn 600 calories per hour no matter how hard I pedal. I don’t get this.

    Is this a flaw in the calculation, or is the reality that the longer you have worked out, the less calories you burn at the same heart rate?

  117. Don

    I appreciate your evaluations!

    I noticed, despite my own lack of expertise, that my calorie burn data was different in a big way once I started using the heart strap with my Garmin 500 Edge. Without the strap, my Garmin showed an amazing amount of calorie burn but my weight never seemed to reflect that burn. Then, once I started using the heart strap, I immediately noticed the burn was far, far lower in calorie burn. I understood intuitively that the unit was more
    accurate when the HR data was involved.

    On a humorous side, a lady bike riding friend recently mentioned that she needed an emotional boost and so she was riding without her heart strap to see a far higher, but far less realistic, calorie burn.

  118. Raju Anantharaman

    I have an issue with Garmin Edge 500. When used with a Garmin Premium HRM, while HR is OK, the calories burnt is awefully wrong. For instance, today I rode 28.46 Km. @ 22.40 Km./Hr. in 1:16. While the averageHR is 143 and the max. 165, the Calories are 5 (repeat 5). Strava, however, records thecalories as 924.

    Has anyone faced a similar issue?

    • Don

      I’m currently using a heart strap for both the Garmin 500 (my original unit) and my newly gifted Garmin 520. The calorie burn numbers for each is somewhat different. Not by huge amounts but different.

      I’m just of the opinion that its best to accept the general idea rather than get too concerned about accuracy down to a few calories. Same as GPS units that provide different distance measurements which my hiking friends always commented about. Each unit had a slightly different idea of distance which generally was no more than a tenth of a mile.

  119. Jim

    Looking at this interesting post, I am wondering if all of the new fitness trackers that measure heart rate (e.g., Fitbit Charge HR) use the method suggest by Firstbeat Technologies? It would seem this would provide the best estimate of calorie burn available though the accuracy of wrist heart beat measurements is not as reliable as those from a chest strap. I’ve been wondering how accurate the calorie estimates are for various activities such as yoga, weight lifting, and biking….sounds like this relatively simple approach would be the best method. I’d be interested in what are your thoughts on this?

  120. Emery

    Is it safe to assume the Fenix 3 works with the 2nd gen algorithm? TIA

  121. Bernard

    Hi DCR,
    Is this a topic you are planning to update in the near future? Or is this the state of the industry?
    I’m asking because I did a training course this week which burned me 1940Cal and I did practicaly 99% the same last week and than burned +3600cal. Both had the same distance and avg. speed. (Actually the one that burned 3600cal. was 2-3K shorter!) The only difference is that yesterday I did slightly more interval training and last week I did a continuous pace.


  122. Marek

    Just looked at my indoor cycling data. I train on Tacx so I get power data. I always have Garmin HRM on me. Tracked 7 workouts, 20-40 min, average HR was from 148 to 161. Then I calculated theoretical calories per minute from power and compared this with calories per minute that I get from Garmin Connect.
    Calories you get from Garmin … there is absolutely NO correlation between HR and calories per minute! But there is perfect correlation between average power and calories per minute. In fact, Garmin calculates the total calories from power and efficiency of 24%. HR or speed is ignored completely!

    • taroon

      after 2 rides on my new kickr snap paired with my 920 (with different hr straps each time – hrm run & scosche rhythm) where the Garmin showed me a woefully low calorie count, I started to suspect this might be the issue.

      I’d be happy to let it calculate based on power but I don’t think my kickr is throwing out accurate power readings either. I’ve run a few spin downs but need to do some reading up I reckon. any ideas?

  123. John Charnock

    Strava reduces the calories significantly when imported from the Garmin portal

    On a recent ride Garmin 2279 calories, when it was imported into Strava it came out at 1270 calories.

    Which one os more accurate ?

    • It depends. Would have to know how long of a ride, effort/intensity, your weight, etc… to even begin to take a stab at it.

    • Jason

      I routinely ride the same area with my club.

      I initially was using the Garmin 500 & HR chest strap.
      Then, I received the Garmin 520 as a gift & ride the same area also with the HR chest strap.

      There is a large difference in the calorie burn count with them, too. The Garmin 500 routinely
      reads a higher burn rate than the 520.

    • John Charnock

      It’s not the actual calories that matter at the moment just the reasons for the large discrepancy between what Garmin says and what Strava calculates. From what you have said, it looks like Strava is taking raw data and using it to calculate its own assessment for calories burned. Whereas MapMyRide takes the calorie data directly from Garmin and therefore MapMyRide and Garmin agree.

      I am 86Kilo, 3 hours of effort at 154bpm / 180bmp and 70Km of riding Strava claims 1200 calories, I am thinking Garmin at 2279 is more realistic

  124. CMP

    My experience with three Garmin devices (Vivoactive, Fenix 2 and Edge 520) has convinced me that Garmin’s HR-based calorie burn calculations are inaccurate and basically worthless. In all cases, for both running and cycling, the Garmin devices with a HR monitor in use produce estimates that, for me at least, are about 60% of those produced by all other references. In some cases–e.g., running on a completely flat course–calorie burn should be relatively easily estimated based on distance and my personal characteristics (age, height, weight). In that situation, online calculators, Strava, and other devices tend to be in rough agreement. The Garmin devices with HR monitor consistently estimate very, very low.

    It isn’t surprising that the attempt to measure calories based on heart rate is a highly fraught exercise. Calorie burn is determined by the amount of work performed over efficiency in converting food calories to work. Heart rate is only indirectly related to the amount of work being done, and the relationship between HR and work performed will vary dramatically from person to person. For example, two individuals of the same weight running a mile at a given pace should burn approximately the same number of calories even though one may be a highly trained elite athlete who is barely breaking a sweat and the other is pushing near his or her max. While Garmin does allow adjustment of user settings that, in theory, should allow some personalization of calorie burn calculations (e.g., “Activity Class” and “VO2 Max” on the Garmin Connect App), changing them doesn’t seem to have much impact on Garmin’s calorie numbers. In my case, the low calorie counts might result from a rather atypical HR range: my resting HR is freakishly low for my age (a circumstance that, unfortunately, does not translate to elite performance).

    As far as I can tell, the only way to disable Garmin’s HR-based calorie calculations is by not using a HR monitor. It would be nice if Garmin allowed some choice or, maybe better yet, abandoned HR-based calculations altogether in favor of attempting to measure the amount of work performed. This would mean giving priority to direct measurements of total energy output as measured by a power meter, if there is one, divided by an efficiency factor (this may, in fact, be what Garmin does; I don’t have a power meter). Where there is no direct measurement, better than HR would be a Strava-like power estimate based on speed, distance, elevation gain and runner/rider characteristics, especially weight. Based on test results I’ve seen around the Internet, Strava’s cycling algorithm seems to be reasonably accurate when measured against power meter measurements, at least when it comes to average power and total energy output for a ride, and, for me, Strava’s calorie burn calculations appear to be much more believable than Garmin with a HR monitor.

    It’s important for me for Garmin to get it right because I use Vivoactive for daily activity tracking and running and link it to Myfitnesspal for calorie management. While one solution would be to use Strava’s calorie burn estimates for runs and rides and Garmin’s for daily activity tracking, there seems to be no good way to do that.

  125. Richard

    I have had a Garmin HR+ for about three weeks. During the last week or so, the “calories burned” values are not just inaccurate, they’re dead wrong ! Today, I did a little housecleaning, packing and then I sat in my car driving for 6 hours. So far, according to my monitor, I have burned 2285 calories. A correct value should be in the 300 to 500 range. Is my unit broken ? The other functions – even the recorded heart rate – all seem to be OK.

    • Dom

      I think you’re not taking into account that the figure includes your base metabolic rate, so you could easily have hit 500 before you got up.

    • Ben Dobson

      Yep, exactly. An average male would easily burn 1800 calories a day, just staying alive even if you lay in bed for 24 hours. Which puts you right on that money with 3-500 active calories on top of that

  126. Occamsrazor

    I just bought a Garmin 520 and am using it with a Scosche Rhythm+ HRM. Having read the above I now realise the Scosche doesn’t do the heart rate variability data which it seems the Firstbeat method needs, or if it does send such data it is a dummy or estimate.

    1.. Is the dummy HRV data the Scosche sends enough to actually engage the Firstbeat method? Is there any way to tell?

    2. If it isn’t, then which of the above methods would it default to? Would it be only the basic speed/distance one meaning there would be no advantage to using the HRM? I’m guessing not as then it should be similar to Strava which it isn’t.

    I did a long singletrack/MTB ride today on bumpy dirt tracks and pushed myself pretty hard throughout. The 520 uploaded to Garmin Connect which then synced to Strava. I’m Male 42yrs 92kg/203lbs 6’4″/1.93m

    Garmin Connect said:

    Distance: 31.39 km
    Avg Speed: 12.7 kph
    Time: 2:28:00
    Elev Gain: 373 m
    Avg Temp: 27.3 °C
    Avg HR: 157 bpm
    Max HR: 181 bpm
    Calories: 2,418 C

    Strava said:

    Distance: 31.3km
    AVG Speed: 15.0km
    Moving Time: 2:05:22
    Elapsed Time: 2:28:01
    Elevation: 373m
    Temperature: 27℃
    AVG Heart Rate: 159bpm
    Max Heart Rate: 180bpm
    Calories: 1,101

    So Garmin said 2,418 calories and Strava said 1,101 which is obviously a big difference. Presumably the Garmin is somehow using the HR data (?) so should be better (?)

    I realise none of these things are very accurate, but am trying to work out which is probably the more realistic.

    • James L

      I looked into this a when I was buying my Garmin watch. A way to compare calorie expenditure is to use the old way which is based on something called The Compendium of Physical Activities Tracking Guide. Basically, this gives the amount of expected calorie usage for different activities per weight and time of exercise. To estimate your calorie expenditure, I used the activity called bicycling, BMX or mountain, your weight of 92 kg, and a time of 2 hours and 20 minutes. The estimated calorie expenditure was 1916 which is closer to the Garmin estimate. You can do a search on line for the Tracking Guide and how to use to see the potential variation by activity. BTW, the estimate scales linearly with weight and time. Hope this helps.

  127. Can you update this post. Very important post but very outdated.

    • Andrew Witchger

      +1 for an update.

      I’d be especially interested in how the new measurements in the fenix 5 compare to myfitnesspal and other calorie tracking services.

  128. Chris

    Do you know which generation of the Firstbeast algorithm is being used on the Edge 520 worth firmware

  129. Greg Judin

    I agree that an update would be very relevant and useful, Ray, not to mention appreciated.

    I am also very curious as to whether there is a way to compare the calculated caloric expenditure using heart rate compared to power meter. I normally always ride with a power meter, and as a result believe my Garmin to always be calculating calories using power, but would be very interested to compare this metric to the calories that would have been calculated using heart rate. Is this possible?

  130. Juan

    Have you thought about revisiting this topic with the advances in sports tech?

  131. Emily

    I would like to see an update. I am currently using the Edge 800 with my New Leaf info. I have considered upgrading to a unit with FIrstBeat, but have not been convinced that it is accurate enough. I like seeing my fat calories and total calories burned. FIrst Beat does not split.

    It would also be nice if Garmin would allow us to input the New Leaf info to the units with FIrst beat.

  132. Jeremy

    Excellent article. Thanks.

    I’ve been using a Garmin 810 but switched to Wahoo Elemnt. Very good user interface on the Wahoo! One thing, when I download a ride it differentiates calories and kjoules, and I manually override the calorie value in Training Peaks and in my food tracking software. Is there a way to make the calorie output number equal the kjoule number so I don’t have to change it manually? Thanks, Jeremy

  133. Metin Emiroglu

    While researching more details about how Firstbeat mechanism works I came across these two references, maybe you’ll find them useful.

    Firstbeat Gets Calorie Counts Right: link to firstbeat.com

    An Energy Expenditure Estimation Method Based on Heart Rate Measurement: link to assets.firstbeat.com

    • Emily

      I just read the article and wonder how does first beat know how much fat vs carbs you are burning? The New Leaf info still seems to be the most accurate. Having an Exercise Metabolic test done is much easier and gives you HR zones and what you are burning in each zone.

  134. Emily

    Is the Device Master Sheet above still accurate today?

    Would appreciate any info.

  135. Don L

    I was wondering how my garmin 920XT came up with calories on a road ride vs a MTB ride. It would seem there is virtually no difference if not using a HR strap. Your article doesn’t mention what software a 920XT is using for calories. I just wanted a rough idea on my effort output based on calories. Will my 920XT with a HR strap get me this vs not using a strap ? ]

    Thank you for you in depth and always informative articles and comparisons.

    Don L

  136. Gareth Roach

    Thanks – sadly you’ve confirmed what i kind of guessed already – I’m using the very basic measurements and there’s no way I am using the calories Garmin suggest! So i will put the biscuits back now…

  137. Pat Sullivan

    Obviously I’m late to the game here, but is the info in this write-up still up-to-date? For instance, is Firstbeat still in use by Garmin? Second gen or later? And what devices does it work with. I will look over your site some more since I find that you consistently provide information that is very helpful and complete.

  138. Will Luttrell

    Would love to see an update on this.

    I just bought the Vector 3 pedals to go with my HRM-Pro and Fenix 6s Pro Solar.

    One of my primary uses of the tech is to track caloric expenditure. Would love to know if the Vectors make the caloric data better, are not used, or completely replace the chest strap and gps caloric data.

  139. Emily Q

    I would like to see Garmin allow us to input the new leaf info on the newer edge. For now I keep my 800. Could you address this with Garmin? Would also like an update to this thread. The newer edge devices do not allow me to see fat calories vs carb calories burned.