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Sleep

Sleep Calculator

Find the best times to wake up by aligning with 90-minute sleep cycles. We add 14 minutes for typical sleep onset.

Sleep Calculator

If you go to bed at the time below, here are the best wake-up times based on 90-minute sleep cycles.

What your result means

Waking at the end of a cycle reduces grogginess. Aim for 5–6 full cycles per night.

How we calculate this

Bedtime + 14 minutes onset + N × 90-minute cycles.

Limitations

Sleep cycles vary individually from about 80 to 110 minutes. Use the suggestions as starting points and adjust based on how you feel.

Frequently asked questions

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Related guides

References

  1. World Health Organization. https://www.who.int
  2. NHS — Health A to Z. https://www.nhs.uk
  3. Centers for Disease Control and Prevention. https://www.cdc.gov

Browse all calculators or read our evidence-based guides.