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Sleep cycle calculator
Find the best time to go to bed or wake up, based on 90-minute sleep cycles.
Go to bed at one of these times:
Ideal
—
6 cycles · 9.0 h of sleep
Great
—
5 cycles · 7.5 h of sleep
Short
—
4 cycles · 6.0 h of sleep
Emergency
—
3 cycles · 4.5 h of sleep
A sleep cycle lasts about 90 minutes. Waking at the end of a cycle, rather than in deep sleep, usually feels easier. We add 15 minutes for the average time it takes to fall asleep. Most adults need 7–9 hours, which is 5 to 6 cycles.
General estimates for educational purposes only — not medical advice. If you have a health condition, talk to a qualified professional.
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