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😴 Sleep Cycle Calculator

Bedtimes and wake times by 90-minute cycles

Loading interactive sleep cycle calculator…

About the Sleep Cycle Calculator

Sleep happens in roughly 90-minute cycles. Waking at the end of a cycle feels easier than waking in the middle of deep sleep.

Tell the calculator when you want to wake up (or fall asleep) and it suggests target times that land on cycle boundaries.

How it works

  1. Pick your desired wake-up or bedtime.
  2. Read the list of suggested cycle-aligned times.
  3. Pick the one that gives you the right number of cycles.

What you'll learn

  • Why total time in bed matters less than complete cycles.
  • How REM and deep sleep stages cycle through the night.

FAQs

How many cycles should I aim for?
Five to six complete cycles (7.5 to 9 hours) suits most adults.

Disclaimer: For general guidance. Persistent sleep issues are worth discussing with a clinician.

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