One of the selling points for any fitness tracker, be it aGarmin,Apple WatchofFitbit, is the amount of data about your body and your overall health it can provide. The ability to track your heart rate, your step count, monitor your sleep or even check your blood oxygen saturation levels and look for irregular heartbeat are all common features.
The best Fitbit fitness trackers you can buy right now
Fitbit devices are useful tools if you’re trying to keep track of your fitness and health. These are our favorite options for every need.
Over the last few years, Fitbit has added features to its hardware and software offerings along with itsPremium serviceoffering, allowing you not only to track what you eat (and the corresponding calories), but also measure your calorie output throughout a day, even if you don’t log a workout.
Have ever wondered how accurate Fitbit’s calorie tracking feature is? We did, so we looked into it.
What does Fitbit say about its calorie tracking capabilities?
Fitbit has adedicated support pagethat lays out all the indicators and metrics it uses to calculate how many calories you’ve burned throughout the day. There are a few key indicators Fitbit uses in its calculation.
First is your basal metabolic rate or BMR. Your BMR is how many calories you burn, naturally, from things like breathing or your heart beating. Basically, it’s a known number of calories you’ll burn each day, without doing anything strenuous. Not everyone’s BMR is the same. Fitbit uses the information you entered about yourself when you set up your account, such as age, sex, height and weight to calculate your BMR.
Your daily activity data is also used in the calculation, such as how many steps you’ve taken and how much you’ve moved around in general.
The final indicator used when calorie tracking is any logged exercises or workouts, combined with information from your Fitbit about your heart rate.
What do experts say about the accuracy of Fitbit’s calorie tracking?
There have been numerous studies done to determine just how accurate Fitbit trackers are at calorie tracking. The results are somewhat mixed, depending on the specific test (walk versus run, for instance), but the overall takeaway is that Fitbit’s calorie tracking feature isn’t very accurate.
“The results are somewhat mixed, depending on the specific test (walk versus run, for instance), but the overall takeaway is that Fitbit’s calorie tracking feature isn’t very accurate.”
In 2019, researchers at Aberystwyth Universitytested the accuracy of three different activity trackers, including a Fitbit Charge 2. The researchers found that the Charge 2 overestimated total calories burned during a 10-minute walk by 53.5%; the worst performance out of the test group. However, after a 10-minute run, the Fitbit was off by just 4.3%; the best performance out of the test group.
Anotherpublished study, this one from 2018, tested Fitbit’s accuracy for “steps, energy expenditure, sleep, time in activity, and distance” in free-living settings and a controlled lab.
After 67 different studies, the conclusion is “discretion should be used when considering the use of Fitbit devices as an outcome measurement tool in research or to inform health care decisions”, citing Fitbit’s inconsistent performance during the study.
Both of the referenced studies are several years old and relied on older Fitbit models that lack improvements made to areas that have a direct impact on calorie tracking, such as the Charge 6’s improved heart rate monitoring features.
How does Fitbit track calories compared to Apple Watch?
I haven’t been able to find any studies that directly compare Fitbit’s calorie tracking capabilities to the Apple Watch, but I can tell you from my own anecdotal experience that when I wear a Fitbit and an Apple Watch at the same time, the Fitbit’s number of burned calories has almost always been higher. It doesn’t matter how active I am, the Fitbit app always shows that I’ve burned more calories. Samsung’s Galaxy watches and Samsung Health also show I’ve burned a lot more calories than the Apple Watch.
I won’t shy away from the fact that when I’ve been struggling to get back into a regular workout routine, I tend to lean on Fitbit’s calorie estimates to motivate me to get going. Seeing a higher number of calories burned makes me feel like I did enough, while the Apple Watch, at times, has left me feeling like I didn’t do enough.
Part of the reason for that is that Apple breaks your burned calories down into two different categories. There’s the Active Energy calories you burn, which is determined by your activity level for the day and any workouts, and then there’s your Resting Energy, which is how many calories you naturally burn without any extra activity.
Another anecdote: After completing a workout out on the Peloton bike, the calorie estimate in the Peloton app is often in line with what the Apple Watch shows me, even when I don’t sync my Apple Watch heart rate sensor with the Peloton.
Can I improve the accuracy of my Fitbit’s calorie tracking?
There are also some steps you may take to help improve the overall accuracy of Fitbit’s calorie counting when using one of its trackers.
Tips and tricks
What is Fitbit Premium and is it worth it?
A Fitbit Premium membership provides access to a range of features and tools that aren’t available to free accounts.
How important is calorie tracking accuracy?
It depends on who you ask. For fitness enthusiasts, it’s probably fair to say that the more accurately a device tracks calories, the better. For others, though, the mere fact that there’s a device on their wrist that gives them an estimate that’s in the general area of the number of calories they’ve burned on a given day is more than enough motivation to continue working towards a goal and being active.
While it’s important, and you surely don’t want something that’s consistently wildly inaccurate, for some (myself included), knowing that there’s a device tracking my activity and I’ll have daily, weekly and monthly results to look at and compare, that’s more than enough motivation to keep me going.
