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Sleep Calculator – Optimize Your Sleep Cycles

Find the best time to sleep or wake up based on 90-minute sleep cycles. Align with your body's natural rhythm to feel refreshed.

Frequently Asked Questions

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Sleep Cycle Calculator

Use this calculator to compute what time to go to bed or get up to wake up refreshed between sleep cycles. The average person takes 15 minutes to fall asleep and has 90-minute sleep cycles.

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About Sleep Cycles

Sleep cycles typically last around 90 minutes, during which your body moves through different stages of sleep:

  • Light Sleep (N1): The transition phase between wakefulness and sleep.
  • Light Sleep (N2): Body temperature drops and heart rate slows.
  • Deep Sleep (N3): The most restorative sleep stage where your body repairs tissues and strengthens the immune system.
  • REM Sleep: Where most dreaming occurs and memory consolidation happens.

Waking up at the end of a sleep cycle, rather than in the middle of deep sleep, can help you feel more refreshed and alert.

Most adults need between 7-9 hours of sleep per night, which is about 4-6 complete sleep cycles.