Sleep Cycle Calculator
Suggests bedtimes for a chosen wake-up time (or wake times for a bedtime) aligned to full sleep cycles, so the alarm lands between cycles instead of in deep sleep.
Read the full guide to this tool
Results
Notes
- A night of 5 cycles (7.5 h of sleep) or 6 cycles (9 h) suits most adults; consistently needing under 4 is a sign to go to bed earlier, not to optimize the alarm.
- Cycle length is an average — treat the suggested times as ±15 minute windows, not precise targets.
- This is an educational estimate, not medical advice; consult a professional for decisions about your health.
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