Each Fitbit in the line has top-notch battery life, lasting days even with auto-activity and auto-sleep tracking turned on, so you don't have to worry about charging it every night.  Officially, the battery for all Fitbits featured lasts from six days up to 10 days, depending on the device and your usage. In my experience, the Versa 2, Versa 3, and Sense last an average of six days on one charge, the Charge 4 for seven days, and the Inspire 2 a whopping 10 days.