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Sleep Calculator
Plan bed or wake times around 90-minute sleep cycles.
Plan around sleep cycles
Uses an approximate 90-minute cycle plus 15 minutes to fall asleep.
I want to…
6 cycles
21:45
9 hours asleep
5 cycles
23:15
7.5 hours asleep
4 cycles
00:45
6 hours asleep
Sleep needs and cycle lengths vary. Most adults generally need 7–9 hours; this planner is not medical advice.
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