What do the calorie fields actually represent?

[rocketslay1]

I have been trying to figure out what the various calorie fields represent (activityCalories, caloriesBMR, caloriesOut, marginalCalories, etc). For example, doing some testing, I found that on a date with no recorded activities or steps, I got different values for caloriesBMR and caloriesOut:

		caloriesBMR => 1587
		caloriesOut => 1477

BMR calories are supposed to be the number of calories spent by your body even if you're doing nothin,g so this doesn't really make any sense. Also, when I did test recording an activity, again with no other steps or data, the activity stated that there were 608 calories burned, but activityCalories was 662, caloriesBMR was 1587, caloriesOut was 2031, and marginalCalories was 480. I can't get these values to square with each other, so does anyone know what these categories really mean? Thanks in advance

[JohnFitbit]

Hi @rocketslay1,

Definitions for these values can be found in the Activity Time-Series documentation:

Calorie Time Series Differences

• activities/calories - The top level time series for calories burned inclusive of BMR, tracked activity, and manually logged activities.

• activities/caloriesBMR - Only BMR calories.

• activities/activityCalories - The number of calories burned during the day for periods of time when the user was active above sedentary level. This value is calculated minute by minute for minutes that fall under this criteria. This includes BMR for those minutes as well as activity burned calories.

• activities/tracker/calories - Calories burned inclusive of BMR according to movement captured by a Fitbit tracker.

• activities/tracker/activityCalories - Calculated similarly to activities/activityCalories, but uses only tracker data. This means that manually logged activities are excluded.

I hope this helps. Let me know if you have any additional questions.