How does the charge 2 calculate calories burned

[Victoria911]

I am struggling to get my head around this.  Calories burned - is this purely on my heart rate and activity or one or the other? 

Apart from the fact that it is not counting all of my steps or floors, so super unimpressed right now.  It also isn't always picking up increased heart rate from activity either.  So despite doing over twice as many steps one day to the next the difference in calories was only 44!  On one day, despite being sat in meetings all day, my heart rate was in the burn zone for most of it (stress) yet only did 7k steps and zero active minutes.  Yesterday, over 15k steps, worked up a fair sweat, over 50 active minutes and burned off an extra 44 cals.

Does it include steps in the calorie calculation?  How is it actually working it out?

[Julia_G]

Hi, @Victoria911, what most people do not realise is that unless they are very athletic, the overwhelming majority of calories they burn is from their body just staying alive.  These calories are called BMR (basal metabolic rate) calories and are the calories burned keeping your heartbeating, your lungs expanding and contracting, your digestion running etc.  Your brain actually burns a lot of calories!

Your BMR calories are calculated based on your age, gender, height and weight (so do make sure this information is correctly entered, including units!). Fitbit uses a pretty standard calculator for determining your BMR calories.  You can check yours using an online calculator or on your Fitbit app you can scroll back to the days from before you started wearing your Fitbit.  You will see that it shows calories for those days -- those will be your BMR calories.

On top of your BMR calories Fitbit calculates calories based on your heartrate -- that is a pretty reliable way of calculating.  If you were very stressed during that meeting, and had an elevated heartrate, you probably will have been burning more calories than usual!

You can read more about how Fitbit calculates calories here

I hope this helps.  Welcome to the Community!

[UncleBobby]

@Julia_G your post is actually more informative than the article you linked to.

[Julia_G]

Hi, @UncleBobby , Thank you!  

However, the post I linked was for general, background information.  If nothing else were needed, there would be no need for a Community Forum.  The forums have lots of extra insights and tips to give.