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Sleep Cycle & Recovery
Find your optimal bedtime or wake-up time based on 90-minute REM sleep cycles.
Hours
:
Minutes
You should try to fall asleep at:
9:16 PM
6 Sleep Cycles
9 Hours
10:46 PM
5 Sleep Cycles
7.5 Hours
12:16 AM
4 Sleep Cycles
6 Hours
Calculations are based on 90-minute REM sleep cycles. Waking up mid-cycle leaves you feeling groggy (sleep inertia), while waking up between cycles makes you feel refreshed.
The 90-Minute Rule
A full sleep cycle lasts about 90 minutes.- $&
Sleep Inertia
Waking up in the middle of deep sleep makes you feel groggy. Aim to wake up at the end of a cycle.Explore More Tools
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