Sleep Cycle Calculator

Calculate bedtimes and wake times aligned to 90-minute sleep cycles.

Find optimal wake-up times by sleep cycles.

How to use

  1. Enter either your desired wake-up time or bedtime.
  2. View suggested times based on 90-minute sleep cycles.
  3. Pick a time that allows full cycles plus fall-asleep buffer.
  4. Use the suggestions to plan a more refreshing sleep schedule.

About Sleep Cycle Calculator

Find optimal wake-up times by sleep cycles.

Runs in your browser — your files and input stay on your device.

Frequently asked questions

Are sleep cycles exactly 90 minutes?

Cycles vary by person. Ninety minutes is a useful average for planning.

Is this medical advice?

No. Consult a sleep specialist for sleep disorders.

Is data stored?

No.

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