Help with Fitbit calories burned?

I think it's because mfp has also calculated the calories you will use in normal life (& takes the deficit from this). At the moment you're not burning extra Fitbit shows all calories you burn (including those from basic functions like breathing).

Mfp will only add extra calories from the Fitbit when the fitbit's estimation of what you will burn in a day is more than mfp's I.e. You're doing more activity than predicted.

Hope this helps and enjoy the charge hr!!

Here's my experience with the numbers between the device and app. (I don't often use the FitBit app itself except to just force-sync the device. I don't much pay attention to the FitBit app numbers.) I have negative calorie adjustments turned on, my activity setting on MFP is set to sedentary, and I've set it to 1/lb per week for the loss rate. (I think the FitBit app is also set to 1/lb per week, but like I said, I don't really use the FitBit app itself.)

In the morning when I wake up, my FitBit device will say I've burned ~400 total calories (because I burn calories while asleep). The MFP app will tell me I have "-100 calories" from exercise. If I never do anything all day, my exercise calorie adjustment in MFP will stay at about negative 100 to zero (even though my FitBit itself at the end of the evening would tell me I've burned 1600-1700 calories total for the day.

HOWEVER, if I walk at lunch or go grocery shopping or just about anything like that, MFP will start showing a calorie adjustment for exercise calories earned. If I walk a couple miles and go grocery shopping, I'll "earn" about 400 calories.

I already know every day that it's likely I'll have an adjustment by the end of the day. Me personally, I use this adjustment for the buffer for my after-dinner snack(s).