Sleep Calculator

Calculate optimal bedtime or wake-up time based on 90-minute sleep cycles. Get better rest by waking between cycles.

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Sleep Calculator
Average person takes 10-20 minutes to fall asleep
About Sleep Cycles

A complete sleep cycle lasts approximately 90 minutes. Waking up at the end of a cycle helps you feel more refreshed.

The average adult needs 4-6 cycles (6-9 hours) per night for optimal rest.

Best bedtimes to wake up refreshed at 7:00 AM
Choose a time that fits 4-6 complete sleep cycles
Recommended Sleep by Age
Age Group Recommended Cycles
Teenagers (14-17) 8-10 hours 5-7 cycles
Young Adults (18-25) 7-9 hours 5-6 cycles
Adults (26-64) 7-9 hours 5-6 cycles
Older Adults (65+) 7-8 hours 5 cycles
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