Is my Charge 2 overestimating my calorie expenditure?

[Unikatze]

I've been steadily gaining weight even though I'm eating at a caloric deficit according to my fitbit. 

Fitbit states I'm burning between 2800 to 3400 calories a day depending on my activity level. And other calculators I've checked based on my age, height, weight and general activity level say I'm more likely burning around 1800-2000. 
So I'm wondering how does fitbit calculate this expenditure. Because it's very likely that while I thought I was eating on deficit I'm in fact eating almost 800 calories over on a daily basis. 

https://www.reuters.com/article/us-health-fitness-tracker-accuracy/how-good-are-activity-trackers-at...

[WavyDavey]

Hi @Unikatze,

For whatever reason, some people find their fitbits can overestimate calories burned. I would subtract 10% more from your calories in, and see the results. It may take some experimentation to find the number you need for weight loss. Best of luck.

[Bill_k]

1800-2000 seems pretty low for someone doing any activity at all. This is the government number used for sedentary activity and the baseline for fitbit with no increased exercise heart rate.

If you are active and showing fat burning heart rates when working or exercising  i'd trust the higher number your fitbit is giving you and cut down your caloric intake to maybe 2000 and see what happens.