Sleep Cycle Calculator

Calculate optimal sleep and wake times based on 90-minute sleep cycles to wake up refreshed

How to Use Sleep Cycle Calculator

1. Choose your mode: "What time should I wake up?" (enter bedtime) or "What time should I go to bed?" (enter desired wake time)
2. Enter your bedtime or wake time, or click Current Time to fill it automatically
3. Review the 6 recommended times — each represents waking up at the end of a sleep cycle. Green-highlighted options (5-6 cycles / 7.5-9 hours) are the most recommended for adults.

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