Everyday
Sleep Cycle Calculator
Best bedtime or wake time based on 90-minute sleep cycles.
Inputs
Sleep Cycle Calculator
Result
Ideal bedtimes
9:45 PM → 2:15 AM
- 6 cycles (9 h) (recommended)
- 9:45 PM
- 5 cycles (7.5 h) (recommended)
- 11:15 PM
- 4 cycles (6 h)
- 12:45 AM
- 3 cycles (4.5 h)
- 2:15 AM
Common questions
Why 90 minutes?
A full sleep cycle averages about 90 minutes. Waking at the end of a cycle (in light sleep) leaves you feeling more refreshed than waking mid-cycle.
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