Sleep Cycle Calculator

Plan possible bedtimes or wake times using approximate sleep cycles and a configurable time to fall asleep.

Sleep Cycle Calculator
Select Method
N (min)
L (min)
Sleep Time
About Sleep Cycle:
  • 1. Sleep cycles refer to the biological rhythm of sleep. A normal sleep cycle consists of two periods: non-REM and REM sleep.
  • 2. Non-REM and REM sleep alternate, with each alternation forming a cycle, usually 90-100 minutes.
  • 3. Non-REM lasts 60-70 minutes, REM lasts 15-30 minutes.
  • 4. Usually, 5 cycles are needed to ensure sleep time and quality, generally 6-8 hours.

ABOUT THIS TOOL

Sleep Cycle Calculator

Sleep cycles are not exactly 90 minutes for every person or every night, so the times shown are planning estimates.