Sleep Cycle Calculator
Find the best bedtime or wake time based on 90-minute sleep cycles
You should go to bed at one of these times:
9:45 PM
6 cycles — 9h sleep
Recommended
11:15 PM
5 cycles — 7.5h sleep
Good
12:45 AM
4 cycles — 6h sleep
2:15 AM
3 cycles — 4.5h sleep
Based on 90-minute sleep cycles + 15 minutes to fall asleep. Waking up between cycles helps you feel refreshed.
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