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Sleep Cycle Calculator

Find the best time to wake up or go to sleep based on 90-minute sleep cycles to wake up refreshed

Best bedtimes to wake up at 07:00 AM

09:46 PM

6 sleep cycles(9 hours of sleep)Optimal

11:16 PM

5 sleep cycles(7.5 hours of sleep)Recommended

12:46 AM

4 sleep cycles(6 hours of sleep)

02:16 AM

3 sleep cycles(4.5 hours of sleep)

03:46 AM

2 sleep cycles(3 hours of sleep)

05:16 AM

1 sleep cycle(1.5 hours of sleep)

A full sleep cycle lasts about 90 minutes and includes light sleep, deep sleep, and REM stages. Waking up at the end of a cycle (instead of mid-cycle) helps you feel more refreshed. Most adults need 4–6 complete cycles per night.

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