Sleep Calculator

What time do you want to wake up?

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If you want to go to bed now...

Go to bed at:

9:45 PM

9h hours of sleep

6 cycles

Recommended

11:15 PM

7h 30m hours of sleep

5 cycles

12:45 AM

6h hours of sleep

4 cycles

2:15 AM

4h 30m hours of sleep

3 cycles

Sleep cycles last about 90 minutes. Waking between cycles helps you feel more refreshed.