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Sleep Cycle Calculator

Generators · tool

Sleep Cycle Calculator

Best times to sleep and wake.

Go to bed at one of these times:

9:45 PM

6 cycles · 9h

11:15 PM

5 cycles · 7.5h

12:45 AM

4 cycles · 6h

2:15 AM

3 cycles · 4.5h

If you go to sleep now (11:17 PM), wake up at:

4:02 AM

3 cycles

5:32 AM

4 cycles

7:02 AM

5 cycles

8:32 AM

6 cycles

A sleep cycle lasts about 90 minutes. Waking between cycles helps you feel less groggy. Adults need 5–6 cycles (7.5–9 hours).

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