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Sleep Calculator

Calculate optimal bedtime or wake time based on 90-minute sleep cycles for better rest quality.

Calculations include 15 minutes to fall asleep. Each sleep cycle is approximately 90 minutes.

How to Use This Sleep Calculator

  1. 1Choose mode: when to sleep or when to wake
  2. 2Enter your target time
  3. 3Click Calculate
  4. 4Choose from recommended times

Formula

Each sleep cycle = 90 minutes. Fall asleep time = 15 minutes. Optimal = 4-6 complete cycles.

Frequently Asked Questions

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About Sleep Calculator

Wake up feeling refreshed by aligning your sleep with natural 90-minute sleep cycles. This calculator accounts for the time it takes to fall asleep.