A few days ago my FB sleep data suddenly changed. Wake times doubled or tripled, REM declined drastically and overall sleep score plummeted 10 or more points. From this forum I gather it is related to some capricious (unannounced/ unexplained) algorithm change last summer. No idea why its just now reaching me, but supect it was due to my recent replacement of a failing Charge 5 with a new Charge 6. Now I have to assume everything I knew, or thought I knew, about my sleep stats is wrong. I've had enough of this BS. I cancelled my Premium subscription this morning.
Best AnswerHello @SleepHead73
The change to the sleep tracking algorithm was announced 01 Aug 2025 & updated on 18 Sep 2025
Android app: https://community.fitbit.com/t5/Android-App/Your-sleep-tracking-just-got-more-accurate/m-p/5808938#M...
Rieko | N California USA MBG PE
Best AnswerWell, yes, if you monitor this community regularly which I don't 😉
Best Answer