It also depends on what you've set your activity level to in MFP. 10k steps might earn a lot of calories for someone who's set to "sedentary", but very few or even negative calories for someone who's set to "active".

brb_2013 wrote: »

I am set to sedentary, and 10k steps adds about 500 calories to my day. Sometimes its more, rarely less. I do not eat those back though because i think its just a part of my day. I weigh over 250lbs and am 5'6''

You are misunderstanding the way MFP works. You absolutely should eat back those calories. MFP has already created your desired deficit to lose X pounds per week, even with those calories added back. If you don't eat them back, you are eating at too steep a deficit, which could be dangerously low and won't be sustainable.

lemonychild wrote: »

I'm under sedentary I'm set to lose 1lbs per week. I'm 162 at 5'7. I get 500 plus cals. I teach and while I'm on my feet I don't find that as strenuous activity. Should I go to lightly active. I understand there will always be some sort of margin of error both from MFP and Fitbit as nothing can know the bodies mechanisim 100% but id like to minimize it

Changing your activity level on MFP is purely a matter of personal preference.

Do you prefer to eat the minimum calories, and then potentially be left with a bunch of calories that you've earned through exercise to eat at night? But never have to worry about negative adjustments? Set to sedentary.

Do you prefer to plan to eat at a calorie level closer to your average, spreading those exercise calories out more during the day, but potentially end up with a negative calorie adjustment on lower activity days that puts you in the red? Set to a higher activity level.

Totally up to you.