Health
Sleep Cycle Calculator
Find the best bedtime or wake-up time based on 90-minute sleep cycles. Wake up refreshed, not groggy.
Time to fall asleep (~15 min) is included.
Suggested bedtimes
9:45 PMBest
6 cycles · 9 hours
11:15 PMBest
5 cycles · 7.5 hours
12:45 AMGood
4 cycles · 6 hours
2:15 AMsleepCalculator.ok
3 cycles · 4.5 hours
Each sleep cycle is approximately 90 minutes. Waking at the end of a cycle helps you feel more rested.
All calculations run locally in your browser.
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