How Accurate is the Apple Watch as a Fitness Tracker?

One of the key features of the Apple Watch is its ability to serve as a fitness tracker, replacing devices made by Fitbit, Nike, Jawbone, and others. Fitness trackers are often quite inaccurate; I’ve tested several, and only the Fitbit One counts steps accurately. Some fitness trackers also have heart rate sensors, as the Apple Watch does, but I’ve never tested any of those.

But how about the Apple Watch? Is it accurate?

I’ve had my Apple Watch for three days, and I’ve been recording my activity, and comparing it to the Fitbit One. I’ve found that, in some ways, the Apple Watch is very accurate; in others, it’s all over the place.

The Apple Watch records different types of metrics, not just steps. While it does keep a step count, it focuses on three metrics to determine your activity. You can see them in the three rings that display on the Apple Watch, and in the Activity app on an iPhone:

Activity rings

The outer ring shows the number of active calories you have expended, and the ring is based on a goal you set (I set mine to 500 calories, and increased it after the Watch prompted me to on Sunday evening). The second ring is active minutes; it is measured against a goal of 30 minutes a day. The third ring is standing time: it measures whether you have stood for at least one minute in each of twelve hours of the day. As you can see, all my rings were will beyond their goals yesterday. When you reach a goal, the end of the ring is at 12 o’clock; as you exceed your goals, the ring keeps turning.

The Activity app also shows you more detail: the number of calories, number of active minutes, workouts (if you’ve used the Workout app on the Apple Watch), and the number of steps you’ve taken, and their distance. It’s this final metric that allows one to compare the Apple Watch with other devices.

Counting Steps

Since I’ve had the Apple Watch, I’ve also been wearing my Fitbit One. On Saturday, the Apple Watch recorded 8,300 steps, and the Fitbit counted 8,480. On Sunday, the Apple Watch counted 7,938 steps, and the Fitbit 8,409. In my tests, fitness trackers that you wear on your wrist are very inaccurate, and all the devices I tested over-counted steps. The Apple Watch, however, is under-counting. The Saturday number was very close, but Sunday’s number was about 5% less. I suspect that the Apple Watch is comparing movement data with what is recorded by the iPhone’s motion co-processor, allowing it to be more accurate than standard wrist-worn devices, but it will never be as accurate as counting steps as a pedometer that you wear on your belt (such as the Fitbit One).

But Apple doesn’t use steps as the main metric; I think the only reason they show the step count is because people are used to seeing this number with a fitness tracker (with the notable exception of the defunct Nike+ Fuelband). Apple is focusing on calories, and that’s the main goal you set.

Counting Calories

Apple and Fitbit clearly use different calculations for calories. The Apple Watch has the advantage of being able to check your heart rate (the only Fitbit device that can do this is the Fitbit Surge). It checks your heart rate every 10 minutes, or more or less continuously when you perform a workout using the Workout app on the watch (unless you’ve put the Workout app in Power Saving Mode, in the settings). But how accurate is the Apple Watch’s heart rate sensor? For the most part, when I check it, the numbers look good. But, at times, it’s way off.

When walking on my treadmill yesterday, I checked my heart rate in the Workout glance on my Apple Watch. At times, it was around 100, which seemed to be correct. But several times, it was very low, such as 64 or 72. At one point, I took my heart rate with Withings’ HealthMate app, which lets you measure your pulse by placing your finger over the camera lens of the iPhone. At the left, the Apple Watch; at the right, the Withings HealthMate app:

Apple watch heart rate   Withings heart rate

Also, one time when I was walking outdoors, I checked my heart rate on the Apple Watch, and it said 153. I took my pulse just in case, but it wasn’t that high, it was around 110. The Apple Watch got the number right a couple of minutes later.

With this in mind, I looked at the calorie calculations for both the Apple Watch and the Fitbit. On Saturday, the Apple Watch credited me with 687 active calories and 3,180 resting calories, for a total of 3,867. The Fitbit app calculated that I burned 2,742 calories. On Sunday, the Apple Watch counted a total of 3,915 calories, compared to 2,752 for the Fitbit app.

I’m not sure how these numbers can be so widely divergent. I tend to think the Fitbit app is more realistic (neither can be accurate, since measuring calories is a bit of black magic). Calorie calculators for my age, sex, and weight, show numbers closer to those of Fitbit.

Counting Active Minutes

Another metric that the Apple Watch counts is active minutes. As Apple says, the Exercise ring:

“displays how many minutes of brisk activity you’ve completed towards a goal of 30 minutes. Every minute of movement that equals or exceeds a brisk walk, whether it’s working out or playing with your kids, counts toward your Exercise goal.”

As such, any brisk walking should count as active minutes. In my tests, I found that I could take a walk at a steady pace, and some of its minutes would count, others not. For example, yesterday evening, I walked outside for 21 minutes, with my heart rate around 105. I was warm, nearly sweating, so I think this counts as brisk. The first 5 minutes were clocked as active, but the rest of the walk wasn’t. If I walk on my treadmill, some of the minutes count, and most don’t.

Apple says that you should calibrate your Apple Watch, for better accuracy. This isn’t complicated: just walk or run outdoors with your iPhone for 20 minutes or more, and the Apple Watch should calibrate using the GPS to determine how long your stride is at different speeds. I’ve done this, twice.

A number of users have chimed in on a long thread on Apple’s support forum. Some people suggest that active minutes depend on your heart rate, that it should be in the aerobic level; that’s not what Apple says. Brisk activity is not aerobic. It’s clear that some activities will pose problems to the Apple Watch. Since it can use GPS to track you, it can determine your pace, and how much distance you cover, when you’re walking or running outdoors. But for indoor activity, such as a treadmill, it can only use the speed of your steps and your heart rate. So, while it will calculate calories for such activities, it won’t calculate active minutes. (Though you can override this with the Workout app by recording your activity as an Other workout. All its minutes will count.)

In addition, I’ve been watching when it records active minutes. Yesterday, for example, it recorded a few active minutes in a supermarket. I wasn’t excited enough about the tomatoes I bought – even though they were very good – to make my heart race for several minutes, yet the Apple Watch counted some of that time as active. Just as it did when I was watering the lawn on Saturday.

The Fitbit records active minutes, presumably just based on pace, since it has no other sensors. On Saturday, it recorded 47 active minutes, and on Sunday, 33. The Apple Watch recorded 31 minutes on Saturday, and 50 on Sunday, but that’s with my using the Workouts app to “force” it to record my minutes on the treadmill, so I can’t really compare which is more accurate.

In a walk I took today on my treadmill, using the Indoor Walk workout, for thirty minutes of activity, only 5 were counted as active. Here’s what my Exercise ring looks like after the walk (I don’t know what I was doing earlier today to get one minute of activity):

IMG 2935  IMG 2934

Since I was walking at a constant pace, with a heart rate that was roughly constant after the first couple of minutes, why didn’t more than six minutes count as exercise? Could it be that the heart rate sensor, which clearly has some issues, meant that it was only accurately recording my heart rate for a few minutes?

If I look at the Health app, it shows several readings per minute for my heart rate. If you look here at 12:44, you can see that it’s clearly not getting it right. It’s worth noting that I’m wearing the watch snugly, so much so that I can’t fit a finger between my band and my wrist, but it’s not too tight either.

Heart rate

There’s also another, longer period, from 12:52 to 12:54, where my recorded heart rate dropped from 100 to 87, then, at 12:55, it went up to 108. It stayed from around 103 to 108 for the remainder of the walk, which ended at 1:00.

Tracking Distance

The Apple Watch also seems to have difficulty recording distance and pace for an indoor workout. This shouldn’t be hard. The Apple Watch knows the approximate length of my stride, especially since I calibrated it outdoors with GPS. So it should calculate distance and pace based on the number of steps I take, multiplied by my stride. In a half-hour walk today, it recorded a distance of 1.5 km, whereas my treadmill recorded 1.7 miles (about 2.7 km). While I was walking, I checked the pace, and it was all over the map, ranging from 20 min/km to just over 9 min/km. I was walking at 3.6 mph, so the actual pace should have been around 10:20 per km. Sometimes the Apple Watch lost track of my pace entirely. I took a number of screenshots while walking; they’re in time order, as you can see in the upper-right corner of each image. (I started my workout around 12:30, and only started looking at the Workouts app after about 20 minutes of walking.)

IMG 2920  IMG 2921  IMG 2923  IMG 2925  IMG 2926  IMG 2928

At the time of this writing, after I walked on my treadmill for a half hour, the Apple Watch shows that I have walked 1.58 miles, and the Health app, where I am able to change the units, shows a total of 2.56 km. The Fitbit app, which simply calculates steps multiplied by stride (based on a stride I measured), says I walked 3.22 km, which matches more correctly with what my treadmill showed. The step count is nearly the same: 3,524 on the Apple Watch, and 3,575 for the Fitbit.

I’ve said before that fitness trackers are more about motivation than accuracy. If they get you to be more active, by prodding you to reach new goals, then they are successful. They should give you reliable data about your activity, though, and not be far off the mark. (I consider that the 5% difference in step count is acceptable.) But they shouldn’t lead you to wonder whether your activity is counted correctly, as the Apple Watch does. Either the Apple Watch is severely flawed in its fitness tracking capabilities, or I received a dud (I’m going to call Apple later to try and find out). I’m curious as to whether other readers have compared the Apple Watch with other fitness trackers, or whether anyone has similar data, reported by the Apple Watch, which just seems wrong. Feel free to post in the comments if you do.

63 thoughts on “How Accurate is the Apple Watch as a Fitness Tracker?

  1. Interesting piece, thanks for the read.
    Health tracking is what I’m finding to be the most compelling element of the Watch, though I’m enjoying it a lot in general.
    I go to the gym a few times a week and cycle relatively long distances on the weekend (100km+). I have used traditional heart rate monitors, Garmin GPS devices and apps like Strava to track activity to date.
    My experiences the last few weeks vary from yours a little, though also with common themes.
    On the whole I’ve found the heart rate tracking to be very accurate. I’ve compared with my chest monitor and found to be within 2 or 3 beats on average – usually the Watch estimates are the lower number. (I wear my watch pretty tight when on the bike/at the gym).
    Couple of times I have had a bit of a lag between ramping up my hear rate and the Watch following – specifically when I’ve looked back on my ride at the start of a full-on sprint, where the Watch took a bit of time longer to pick up on the sudden spike in my rate. But most times it tracked reasonably well and in terms of ride metrics as a whole, the native Watch app has been far beyond what I’ve found from Strava’s initial offering.
    The exercise ring confuses me a bit, I have had a similar experience to you so far. For me it certainly underestimates the minutes it thinks I was exercising compared to actuals. Less so with running/cycling, but brisk walking and ‘Other’ gym activity, it has regularly shown minutes less than I expected- I would prefer this to overestimating but it’s not ideal.
    The stand ring confuses me further. I’ll often have to do a lot more than stand and walk to register the minute’s activity, even swinging my arms around and being overly pronounced on my walking style doesn’t always work which can be frustrating as the final minutes of an hour tick by.
    That said, it’s the best all-purpose tracker I’ve used, and I’ve tried a few. One, because it’s alway on my wrist due to all the other value add functions I get from the Watch besides health. Two, because 90% of the time it is ‘accurate enough’ , which for me overrides the glitches – and other trackers I’ve used have had their own misgivings. Three because it’s simple and instantly viewable. Sometimes a bit too simple for my wants, but I appreciate this is a first offering and the majority of users are being targeted, not the specialists (though I use that term very loosely for myself). But the fact the data is just there in real time in a friendly format on watch or Phone, I have found much more useful than going through the process of synching devices or downloading data before being able to review results. Finally, the game-ification element is fun. The rings can be as madenning as they are motivating, but I still want to complete them each day, for now at least, which adds an extra dimension for me personally.
    Apologies for the lengthy post, but thought was a very interesting topic and one I hope Apple really deep-dive over coming generations.

    • Hello

      I discovered another problem with the iWatch. I turned on the “other” selection from the exercise app during my dance class. I forgot to turn it off, drove home, crashed in front of the television and was essentially motionless for over an hour.

      The app continued to give me a higher calorie burn and exercise minutes. I have tried this at random times when I am doing very little and if the exercise app is on it gives both minutes and calories.

      So, I doubt the accuracy of this app when you are exercising since the default is to give both calories and minutes even when you are stationary with a normal heart rate.


  2. apple watch checks heart rate every 10 minutes when not exercising, not every 30.

    The active minute thing is REALLY annoying, and I heartily agree with you.

    if your heart rate was not correct, then it may be that you should wear the watch tighter. That fixed it for me. I like a loose watch, I had to tighten apple watch 2 holes tighter and then it seemed to work flawlessly for heart rate while exercising. It needs to be very snug, I think sweat makes the sensors read less accurately and the watch can’t move at all or it won’t work as well

    • You’re right, it is every ten minutes. I had read thirty minutes a long time ago, but I checked on Apple’s site. I’ll fix that.

      I wear the watch snug enough; if not, the heart rate wouldn’t be picked up at all. As for sweat, if that were the case, it would degrade as you work out, and I’m not seeing that; I’m only seeing that, several times during the workout, it gets very wrong for several minutes.

      • since you’ve only had the watch a few days, the following may not apply to you, but i thought i’d share my experience anyway: for the first couple of weeks, the heart measurements were consistent and steady during my brisk walks. as of a couple of days ago. the heart rate readings started bouncing all over the place, varying by +-50% during an outdoor walk workout. i ended up wiping off the sensor with a lens cloth (and later, rinsed it off more completely with water) and since then, my heart rate measurement has been consistent again.

        • the fitbit will not count steps in the pool, i move my arms and do not get it wet, will the watch count my steps in the pool, I will not immerse?

  3. From my own experience with exercise, and what I read in the article, I would not trade my chest heart rate monitor for any of the devices mentioned. The reason is that accurate heart rate over a given time is a better gauge of overall fitness, and also during an individual workout. If you don’t have that, and it is clear that all these devices are inconsistent, then you cannot form an opinion from the results they give. These are electronic devices and therefore should be precise in their measurements. That makes them like toys or games, and only vaguely useful. Especially for the money involved.

    Its good that Apple is moving into this area at last, and given their history of improvement beyond the first edition of a product I will watch how it progresses, but for now will stick with my $50 strap and an iPhone app. Thanks for the article, very informative.

  4. DC Rainmaker has one in for testing. Once he’s completed his regular battery of tests, I think we will get a clearer idea of where the Apple Watch is today regarding its health and fitness features.

  5. I have had the apple watch since the first day and bought it mostly for health reasons. I run, swim and cycle as well as weights and zumba etc. In other words I am very active everyday for a 64 yr old woman. a few years ago I had a fitbit, but lost the tiny thing. I do have a Garmin for running but because it charges in my office I sometimes forget it. And it has to be fully charged to pick up GPS. Never been happy with it. So as far as running I am pleased overall with the watch. I tried 3rd party apps but they don’t seem as good as the native run app apple provides. But I don’t think it is accurate for my pace. I also use a Moov device strapped to my ankle and a few times my Garmin on my other wrist. Apple watch is never the same for pace. It will be over 12 /mile when I am running hard and know I am around 9:30 or at least somewhere under 10. I should say in the final results it is closer to the real pace overall , but on the display while running the time is all over the place and not even close.

    Today I did a quick 5 miles at lunchtime on the bike. Hard to start the apple watch and the Moov app at same time but it is as close as I could get.Actually the watch was pretty accurate. It said I did 32:01 min and Moov said 32:03; watch said I went 5.2 miles; Moov said 5.3; Apple said my ave speed was 9.99 mph ( cycling is my pleasure sport; I spend more time on running and swimming); Moov said my speed was 9.7mph. For me, in terms of pleasure biking, the watch seems good enough.

    I too found that the heart rate is monitored by apple more frequently when you use a workout app, even if it is just “other”. But after my long run and having already completed my”30 min circle” I am not too concerned about getting more credit. All seems to balance out.The workout apps use more battery power because of the heart rate monitoring all the time. Even though I have not run out of battery power, I do take the watch up after a workout and charge it while I am showering.Just gives it an added boost.

    I love the stand feature as after a long morning workout I tend to sit a lot the rest of the day. So now I get up more often. Sometimes the watch prompts me at times I could have sworn I was just up. So relying on one’s own memory is not very good.I too find sometimes I ave to walk around a lot to get it to say I “passed”. I too swing my arms etc. Crazy to see me do this at 10PM at night while watching TV. My husband thinks I am nuts.

    I wish apple would realize that those of us working out a lot need rest periods and days. So it is hard to get a week’s worth of calories burned awards as on Sundays I take it easy. I could set my calories burned for the day lower but then on workout days I would pass the goal too quickly.

    I have written to apple about being able to add workouts to the watch . I swim vigorously with a coach 2 times a week in a Master’s class. We swim about 2 miles. I know I can add the workout to my Health app but this doesn’t translate to my watch rings. So on 2 days of the weeks it looks like I am a slacker and it is harder to close the exercise ring.

    But I am sure all this will be figured out soon. I am a happy early apple watch user.

    • Hi Ellen. Instant pace is a very tricky metric to get right. Because there is an inherent delay in GPS data, instant pace will be extrapolated from what you were doing in the last few seconds assuming you have a good GPS signal.

      Garmin’s recommendation is to use a calibrated footpod or running dynamics HRM strap in addition to the GPS watch when running or a separate speed sensor when cycling.

      When you hit the lap button or end the workout the device will be able to recalculate a pretty good pace number using GPS for the lap or workout because it knows how far you went and how long it took.

  6. I knew this would prompt some good feedback and have been checking back daily…thanks Kirk, Ellen, Greg and the rest of the folks providing feedback.

    • My Apple watch running iOS 8.3 records all measurements for outdoor walking and bicycling great … indoor walking is good but not on a treadmill … treadmill measurements seem to be off 100% for distance and calories. Also the stride measurement is absurd.

  7. Great article just waiting for my watch as I’m keen to use it over my Fitbit. Keen to see what reply you get from apple. Thank you

  8. Just wanted to point out that FitBit actually has two products that measure heart rate: the FitBit Surge AND the Charge HR. You only mentioned the Surge.

    • Thank you for pointing that out. I have had the Flex w/o HR of course and now wear the Charge HR both wrist wearables. In my opinion this is not apples to apples comparison because you have to compare a wrist tracker to a wrist tracker. No wearable will be 100% accurate.

      There are too many variables plus most super active types already know most of the data these devices give. Its the beginner and novice person who wants to be more active that benefits the most. To me the Apple watch has more bells and whistles in one package so it makes for a more user friendly experiences if you are already a iPhone user.

      If I did not own an iPhone I would not buy it and just stick with Surge or Charge HR for basic data. also the last thing is people forget that these trackers are just tools for fitness. They will not make you eat better in conjunction with exercise. So if you do not do that you will get frustrated if you think activity alone is all you need.

  9. I trust the FitBit One for step count and I enjoy the friends feature that keeps one motivated. I suffer from arterial fibrillation (AF) as do many other people and therefore take a beta-blocker twice daily. This tends to limit my heart rate even when very active (unless AF has kicked in). I don’t see how my Apple Watch can take that into account at the moment.

    • Yes, I think Apple’s threshold for “exercise” should be flexible for people with your condition, or people who simply cannot reach their threshold because of other conditions. I’ll be writing something about that soon.

  10. Hi Kirk,

    This is from the Apple Watch User Guide:

    “Outdoor and Indoor Walk/Run/Cycle are distinct workouts because Apple Watch calculates the calorie burn differently for each. For indoor workouts, Apple Watch relies mainly on your heart rate readings for calorie estimates, but for outdoor workouts, Apple Watch works in conjunction with iPhone (which has GPS) to calculate speed and distance. Those values, along with your heart rate, are used to estimate the number of calories burned.”

    Also, this:

    “If you’re measuring calories or time, you can leave iPhone behind and exercise with just Apple Watch. But for the most accurate distance measurements outdoors, take iPhone along.”

    And if you can save power by disabling the heart rate sensor in the companion iPhone app during long walking and running workouts, your calorie burn estimates might not be as accurate.

    Would you be so kind as to clarify this in your post?

    • While Apple may claim that, it’s certainly not true. I took a twenty minute walk outside two evenings ago, and six minutes counted as exercise. My pace was regular, and I had my phone with me. And when I walk on my treadmill, it counts some active minutes, and they don’t correlate with the minutes when my heart rate is highest.

      What it should be doing is using the accelerometer to see how many steps you take per minute. That’s a good metric to compare with standard walking.

      And the calorie measurements are very, very wrong; not just for me, but a lot of users are reporting this.

  11. I have found my apple watch calorie count to be over 1000 calories more than my fitbit that I have worn continuously for the last 3 years (I have a fitbit charge HR). I, and others, have complained to apple support and been told they are aware of the problem.

    The biggest problem seems to start with their resting calories. Apple gives me 2700 calories for resting calories. I would gain so much weight if I ate up these calories!

    Go to submit a complaint if you want to see anything done about this in the near future.

    • Yes, it’s clearly the resting calories that are way off. I’ve got a case open with Apple about the fitness numbers.

  12. I’ve noticed the same problem with indoor walks that you mentioned. The distance my watch records is about half the distance the treadmill estimates. I have calibrated the watch twice out of doors.

  13. Great article; thanks!

    Here’s my contribution to findings.

    Wahoo Fitness with chest strap reports 485 calories burned on a 43 minute treadmill walk with an average heart rate of 124, 13.5 of those minutes were sustained over 133 bpm.

    Apple Watch, using Indoor Walk in the Workout app, reports 126 average bpm, which is close enough for me. There were no gaps in the heart rate monitoring during the course of the workout. In the end, total calories burned was 228, 78 of those were resting.

    If anything, the watch stats are demoralizing or Wahoo has been feeding my ego for well over a year now. Either way, I’m not sure how the figures can be so (e.g. ~260 cals) different.

    Should I set the Wirkout app to Other? If so, what’s the point of the Indoor Walk setting?

    Happy Exercising!

    • Yes, I wonder about that “Indoor walk” workout too. I’m not sure I see the point of it. Interesting that the Apple Watch underestimates the calories; I’ve heard from people with exercise bikes and treadmills saying the watch overestimates.

      • I have tried the OTHER and it tracks the time and it will count whatever time it taken for Activity. But then like the author says what’s the point. I’m finding it challenge to get all my time counted for a brisk walk.

    • I received the watch for Christmas. I use the Wahoo app with the TICKR strap. I find that the calorie burn is totally different. Watch is much lower. About 30%. Thoughts?

  14. Thanks for the post and the updates, and also all the great comments! When I first got my Watch and had not yet started the Workout App, things were pretty great — steps were with 10% or so of the FitBit Flex I’d been wearing for a few months, and outdoor walks around the block counted most of their duration towards my Exercise goal. I didn’t have the Stand problem people describe, but I’m a twitchy person who can’t sit still so that’s not surprising. What is surprising is what happened when I started using the Workout App and a treadmill. It got worse and worse about counting Exercise minutes, to the point where even leaving the Workout App off and just walking around the block (definition of a brisk walk! It was raining and I wanted to get back home) counted exactly 1 minute (out of slightly more than 20) towards Exercise. I’d take a hammer to it — or return it — except I _LOVE_ the Watch face with outside temp and next item on the calendar. The brief notifications for messages, phone calls, etc. are also wonderful. But as a general fitness tracker, at the moment it is no better than the FitBit Flex, which was a LOT cheaper! I hope this gets fixed, but I’m not optimistic, because all the feedback I’m seeing from Apple is “go calibrate it by taking a 20 minute walk outside with your phone” and I’m like, _that’s all I ever do_.

  15. Hi there,

    Here’s a follow up to my earlier post with some information on using Other in the Workout app, rather than Indoor Walk while walking on a treadmill.

    I usually do a 40-45 minute walk and try to maintain a 133 bpm heart rate using the Wahoo fitness app with a chest strap.

    With the Apple Watch, I’ve set a 350 calorie goal and then there’s the 30 minute exercise goal.

    I’ve kept an eye on the heart rates on both devices, and they are close enough, it seems to me.

    When doing an Indoor Walk workout, I have burned 228 total calories at 79/149 resting/active. Only 4 minutes of exercise are recorded.

    When I set the workout app to Other, the figures are decidedly different. For example: a total of 357 calories at 80/277 resting/active. Also, the total time of the exercise is being recorded at 40+ mins.

    What’s also, somewhat satisfying is that I actually can now complete my move and exercise goals. This is in spite of the fact that the Watch still records far fewer calories burnt than are seen by the Wahoo Fitness app @ 527 total calories.

    While this is an improvement, I simply have no idea which of the two fitness devices is more accurate, nor do I see the purpose of the Indoor Walk app when it doesn’t seem to acknowledge most of my time walking on the treadmill.

    Lastly, I can’t quite figure out how the data being sourced from the Apple Watch and the Wahoo Fitness App are combining in the Apple Health App. For example, Active Calories seems only seems to reflect the Apple Watch data while ignoring the data from the Wahoo Fitness app, and there doesn’t seem to be a way to turn it off. Also, there seems to be zero calories being recorded into the Resting Calories, and there seems to be no way to add the Apple Watch as a data source for that.

    Anyhow, just sharing my observations with the hope that I will hopefully feel comfortable using the Apple Watch as a trusted guide toward my fitness goals.

    Happy Exercising!



    • Thanks for that. In the Health app, have you set priorities for the Wahoo? This tells Health to record that device rather than the iPhone or watch.

      I agree about the Indoor Walk workout; what’s the point if it doesn’t register activity as exercise?

      As for the discrepancy in calories, it’s hard to know which device will be close to accurate. I think it’s safe to assume that none are. :-)

  16. Hi Kirk,

    Thanks for the tip on priorities… I hadn’t read the small print under Active Calories => Share Data, where it says: “… one data source will be chosen based on the priority order listed above.” I just needed to edit and slide Wahoo Fitness to the top.

    I still can’t figure out why resting calories don’t populate, but I’ve setup a call with Apple to ask them about it.

  17. Hi Kirk,

    I have had my watch for a week. My gym visits are 2+ hours, 4 days a week. I ride the stationery bike for 9 miles at a 14 setting, which equates to climbing 4800′. Rpm’s 80, speed 18mph. I set the exercise function on indoor cycle. Watch recorded 1.25 miles. Heart rate is virtually identical to that provided by the bike. I also lift for 1:15-1:45 and record that as other. Heart rate seems consistent between periods of activity and rest. Accuracy and ease of use are important, as to stationary cycling…not. I’m interested to hear apples reply to you. Curious to know how they would measure miles on the stationary bike. Accelerometer in phone, watch, joint data? Heart rate?When I would ride with my phone previously, that 30 mins generally translated to 7500-8000 steps.

  18. Kirk,

    You said you calibrated it outside but did you use the workout app while exercising outside? I have found that I have to use an outdoor run and walk in the workout app to get the stride to be closer. It is still wrong as compared to my treadmill distance but it is much closer.

    • Yes, I calibrated it with the outdoor walk workout, and then tried using the indoor walk workout, and it was very far off in distance.

  19. Your article was reassuring, Kirk, thanks! Was flummoxed by the exact same thing with lawn mowing and heavy exercise. Moving a wood pile also counted more than a 40 minute (near jog) walk. And it is apparent after owning the Fitbit One, Omron pedometer (which I still use) and Fitbit Charge– if it isn’t strapped to your leg, it isn’t measuring steps accurately. Now that I’ve had the Apple Watch a month I’m learning what to expect, although accuracy would be preferable. Worst case scenario is it’s a good motivator regardless.

    Also surprised people are still complaining a lot about battery life. That has been the least of my concerns (and still a complaint for my iPhone).

  20. HemiDj

    I am a 67 year old male tennis player that ordered the 42mm Sport Apple watch 45 minutes after it went on sale, and got an e-mail from Apple that my watch would be delivered in June. The watch came on 26th May, and I started wearing it that afternoon to play tennis, and would put my 6 plus iPhone in my pocket while I played, so it would count my steps, but now there is no need to do that since the watch did it also.

    The watch came with an App that tracked calories, exercise minutes and the number of times I stand. I found by walking at a fast pace about 18 minutes per mile, I burn about 100 calories per mile, and about 70 calories per mile playing tennis, so I walk much more than I play tennis in order to loose the extra 30 pounds of fat that have for the longest time. Yesterday my weight showed that I lost 10 pounds in four weeks, due to tracking my calories burned each day at about 700 calories.

    This is the best investment I have made to getting healthy, since I can not afford a personal coach and like new technology.

  21. Did you ever get a response from Apple? I might have missed your update; I apologize if you posted it already. I am trying to lose weight so accuracy in workouts and active calories is very important to me. I’m wondering whether it makes more sense to go back to my old Bodybugg or stick with the Apple watch in hopes that it will get more accurate (and trusted to be accurate, since it’s hard to know what to believe now).

      • Did you get anything about heart rate monitor? Did they say anything about what is the main reason of these bugs? I mean its software related or do they have hardware issue?

        • I haven’t been able to find out. Apple did hobble the heart rate monitor in the WatchOS update, but as to whether it’s a hardware or software issue isn’t clear.

  22. Correct me if I am wrong, the workout app should provide more accurate data when it is ON rather than the normal watch function?

    I tried a test over 8 hours with the workout app set to Other and continued my normal weekday, drive to the office, sit most of the day, walk a little bit and drive home – all in all pretty lethargic in terms of exercise.

    The apple watch recorded I burned off almost 1700 Calories in this entire time, whereas without using the workout app, I was barely touching 200 Calories.

    Something isn’t quite right here….

  23. My Apple Watch FitPort congratulated me for reaching 10 out of 12 “stand” hours. The problem is that I had only had the watch on for 8 1/2 hours and I took a 90 minute nap today and I spent a couple of hours seated at the computer. Also, I can’t seem to get any kind of FitPort credit for hitting 230 golf balls off the tee at the driving range or for several daily 2 minute sessions of planking. I think Apple has some work to do on this app.

    • I walked for 2 hours using the workout and while it was a leisurely walk (2.5 mph), activity only says 33 minutes of exercise. Shouldn’t it connect to the data from the workout app?
      Did you ever hear back from Apple on these issues? I bought the watch primarily as a fitness tracker and it’s fairly useless in its data accuracy.

  24. I also have been comparing the fitbit one with the apple watch for calorie tracking. The fitbit is extremely accurate calorie-wise. If you count your calories, like me, burning 3500 calories results in a 1 lb loss of body fat (measured with a caliper). Based on the apple watch, I burned 4293 calories, but I only lost .9 lb of fat. So basically it seems to be overestimating caloric burn for me by 172 calories/day on average. This was just a preliminary test, we’ll see if it gets more accurate as time passes. Just wanted to share for those who need accurate calorie data.

  25. Hello, great article! Question for the folks that report that the Apple Watch takes a heart rate reading every 10 or 30 minutes – is that observed or stated? Reason I ask is that when I check my Health app, the frequency/interval of the HR readings seems extremely spotty and random. Sometimes it seems like it might be every 20 minutes, other times it appears to go over an hour without taking a reading.

    However, it does appear that when I’ve let it know I’m IN a workout (via the Workout app), it then takes 2-3 readings per minute. Better than the random-interval readings throughout the day, but probably still nowhere near the same number of readings my chest strap unit is taking. I get that the Apple Watch tires easily and has to be frugal about when it does these things, but a reliable interval would be nice.

    Comparing the calories burned between Apple’s Workout app and the DigitFit app (paired with a Polar chest strap unit) for a strength workout, the Apple Workout app reported almost 100 fewer calories burned than the DigiFit app. The Workout app also reported a slightly lower average HR than the DigiFit app/Polar chest strap) did. Also, to obtain max/min heart rates achieved during the workout, I needed to scroll through the many readings in the Health app on the iPhone – as opposed to just having the min/max HR (and a few other handy data points) listed in the DigiFit

    At this early stage (Day 2 with the Apple Watch), I’m with some of the other reviewers in that I’ll stick with a dedicated bluetooth chest strap and DigiFit app for my information needs.

    • In another article, I explain that Apple changed the way the Apple Watch records your heartbeat. It checks every 10 minutes, but not if you’re moving. Apple had to change because the readings were so unreliable. If you are doing a workout, though, then it checks pretty much constantly, but I find the readings still vary greatly.As for calories, it’s been better since the release of WatchOS 2 – resting calories are not as ridiculous – but it will always differ from the numbers that other devices give.

      • Thanks, Kirk. I’d be interested in that article if you have the link to it handy.

        When you say it checks every 10 min, but not if you’re moving – does that mean that if you happen to be moving (say, walking and swinging your arms) when the 10 minute measurement interval comes up, it skips that measurement and tries again in 10 minutes? And it will keep doing that until it finds that you are motionless for an accurate reading?

        Thanks for the clarification!

  26. 12-7-2015
    This morning I rode my lemond spin bike at home (indoors, of course) for 50 minutes with my new Apple Watch and a chest strap connected to the lemond pilot device on the spin bike. Apple Watch says I burned 295 calories. Chest strap and pilot say I burned 484 calories. That’s nearly a 200-calori difference! When I entered the indoor bike ride into the My Fitness Pal app, it estimated that I burned 484 as well (usually, MFP calculates the calorie burn at just slightly less than the chest strap and pilot). This seems to indicate that the Apple Watch is calculating the calorie burn too low for the indoor bike. This is dismaying, given the cost of the device.

    I hope apple folks are aware of this discussion resource. I will try the “Other” setting and see if it calculates the calorie burn differently. Very glad this site and discussion exists. Thanks.

    • On 12-9-2015, I tried the Other setting on my Apple Watch, sub-set for the open-ended workout, for my ride on my lemond spin bike. No difference from the Apple Watch indoor cycling setting as far as the calorie calculation was concerned.
      Next, I tried using the Other/Open-ended setting to see how the watch tracked my heart rate, which it should be doing constantly when using the workout feature. It showed an accurate heart rate and, just as often, a clearly-wrong heart rate — much too high or much too low, or “measuring” (aka no reading). I’m dismayed at the watch’s poor performance in this feature. And my watch band was as tight as possible. Sigh. Any suggestions would be appreciated. Thanks again for the forum.

  27. I just got my Apple Watch a month ago. Those three rings were driving me crazy trying to figure out the logic behind them and how to change the settings for each. So I was online looking for more details about how the activity and workout modes work, when I came across your post.

    Some of your post is over my head, but you look like you are doing a very thorough job of checking into the accuracy of the watch and the best ways to record activity, so I’ll keep watching your posts in an effort to learn how all this works.

    I use the Lose It app to count calories so I’m especially interested in how the Health Kit Workout and Steps sync over and effect my ratio of ‘calories burned to calories eaten’ on my Lose It app.

  28. So frustrated – just got the apple watch and wore it to my regular workout – a vigorous kettle bell class – and it recorded me as working out for 7 minutes.
    If I can’t figure out a way to get a more accurate read, I may not keep the watch…. searching for a solution.

  29. My husband and I both have the iWatch and we walked around the city yesterday and I registered as doing less km’s than him! We went exactly to the same place. I know maybe he made more steps but not as much as what was recorded. I am still trying to figure out if the iWatch is accurate.

  30. It’s been about 8 months since the original post. I’d be curious to know what Apple’s response was? I’ve had my watch for a month. Only got it for the fitness tracking and it’s completely inaccurate. I say this as I wear my Polar Heart Rate monitor when working out and the steps, calories, distance and minutes differ from watch. Very frustrating. Thankfully I meet all my goals so don’t pay for that watch but if I did it would completely not be worth it

  31. I have just closed 4 cases with Apple genius tech support. Spent more than 5-6 hours with different Geniuses and finally my call my was escalated to T2 tech support and now I am talking to real engineers.
    Simply apple watch cannot track your indoor or outdoor walking properly. I am not talking about accuracy in distance or accuracy as in steps. Very simply, I am talking about how many minutes I have walked (outdoors) today and how many minutes it reports at the end of the day in total exercise minutes. Well good luck! I have taken screenshots, recordings comparison etc just to prove them that it is really buggy and not wort wearing this if you are trying to keep yourself active and motivated because you cannot.
    I have sowed them that I have completed 45mins of brisk walk outdoors and the green exercise circle only reports 2mins of it.
    Another day I have walked over 1hr and only 17mins were reported.
    My average pace is 20:00 min/mile which is something like 2.8 2.9 mile per hour. But of course it changes, sometimes I am walking up a hill or slow the tempo down for 2-3mins and try to keep it up to fast pace again. Like any other walking exercise.
    Well, the explanation was very funny. Apparently apple watch doesn’t count these walking sessions as exercise because sometimes I slow down and my speed is under 3mhp. I started laughing because their explanation was “Yes sir but technically outdoor walking is more than 3mph so it doesn’t count”
    I couldn’t really believe this logic and asked them “Ok so what is all that 128 avg heart beat during this whole 45mins of time and the GPS recording which obviously proves that I ‘ve been walking and sweating like p*g and watch doesn’t like what I did?”
    They couldn’t say anything and kept saying same thing which I should walking at least 3mph avg during the whole outdoor walking ;).

    I have reported this to Apple but I don’t know if they fix this issue or not.
    I am an 43 yrs old man with disability and just trying to be healthy . That’s why it is really important for me to track these thing down because it motivates but looks like Apple doesn’t like 43 year old man with disability trying to walk ;)

  32. Has anyone found a good app for the Apple watch that will add workouts or calories burned when not wearing the watch? eg. adding in a swim workout or weights at the gym?

    When cross training which method of recording the workout is most accurate?

    I have not seen it explicitly stated but I have assumed that the height, weight and other information entered when setting up the watch is taken into account when using the workout functions?

    Thanks! :-)

  33. I really enjoyed this article. Well done!! Strangely. I’ve had the opposite experience with my Apple Watch 3 (compared to other devices), I found that the AW3 consistently underestimates my calorie burn but I guess I’d prefer this than the opposite scenario.

    The brisk walking not consistently counting as exercise doesn’t really bother me, as I don’t really consider it exercise either.

    The only disappointment is that I feel like it AW3 really does underestimate my squash burn. I will play a hard competitive game of squash for 45min (average heat rate of 130+) and it will say I only burned 300 calories. My FitBit would track a similar workout at almost 700. Oh well – Otherwise I am thrilled with the watch. Love the HRR and HRV features.

  34. Thanks for writing this.

    My experience is very different. I tried 2 different fitbits, gained weight on both, and a Garmin, which was ok, but I didn’t like wearing a chest strap.

    I will say, there’s way more to it than your heart beat. That’s only one indication of your activity. But, I find Apple Watch to be incredibly accurate. For a while, I worked out with my Apple Watch on. And, on a calorie restriction, I ate back the exercise calories the watch recorded and I lost weight. This was on a 500/day calorie restriction. So, nothing crazy. Accuracy has to be there for only 500 less per day. And it worked really well.

    Also, it’s true that over time, it learns. So, it can take some time to dial things in. It took months before I felt I was getting accurate data from my activities.

    I don’t eat back exercise calories at the moment, so the calorie burn is a simple indicator for me.

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