Questions about Calories burned accuracy

[Klane25]

Hi I wonder if someone can help.

I have a Fitbit Zip and I am struggling to understand how my Calories burned are being calculated one day to the next.

So on Monday I only did 1,049 steps and Calories burned says 2,271.

However on Tuesday I did 5,801 steps and yet calories burned says 2,752.

I understand the basic concept that its calculated on BMR but this has not changed over they 2 days and these figures are so close for varying activities.

So far today 2,492 steps and 1,099 cals burned!

I am trying to use this data to monitor calories in vs calories out so its important to me that i understand how it works.

Thanks

Moderator edit: Updated subject for clarity.

[SteveH]

I think the problem might be those BMR calories. As you say they are burnt at a constant rate day to day but they also form the bulk of a many people's total calorie burn. For example, I burn around 2000 calories in total each day but 1400 of those will be BMR calories. 

This means that the calories you burn for the steps do not play a very large factor in your total calories so a big jump in steps only gives a small jump in calories.

If you look at your calorie burn for a time when you are asleep this will be just your BMR calories. If you take this off the calories burned data you have it will leave just the calories burned by your activity and hopefully the data will then look more reasonable.

edit: also, don't forget that the calories for today include the BMR calories from midnight

[Sami2066]

I've been reading posts regarding various inconsistencies data issue's.  These seem to range from 2015 to current issues (mine) 2018.  There seems to be no fix.  I have been wearing my Alta HR less and less because I have no confidence in it at all.  At the moment I won't be upgrading or sucked in to a new Fitbit!!!   Very unhappy....

[YojanaFitbit · Accepted solution]

Welcome to the Forums @Klane25 and @Sami2066. Thanks for jumping in @SteveH. 

Thanks for sharing your concerns about the accuracy of yourFitbit. You can find some good details about how this feature works in this master post. Also check these help articles about accuracy:

• How does Fitbit estimate how many calories I've burned?
• How does my Fitbit device calculate my daily activity?

Hope this helps, let me know if you have questions.