Sleep CyclesTwo ModesScience-BasedFree
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We'll calculate the best bedtimes based on 90-minute sleep cycles. Includes ~14 minutes to fall asleep.
Why 90-minute cycles? A complete sleep cycle (light sleep, deep sleep, REM) takes about 90 minutes. Waking between cycles leaves you feeling refreshed instead of groggy.
How many cycles? Most adults need 5-6 cycles (7.5-9 hours) per night. 4 cycles (6 hours) is the minimum for short-term use.
Frequently Asked Questions
Why 90-minute cycles?
A complete sleep cycle includes light sleep, deep sleep, and REM sleep, and takes approximately 90 minutes. Waking between cycles helps you feel more refreshed.
How many cycles do I need?
Most adults need 5-6 cycles (7.5-9 hours). 4 cycles (6 hours) is the minimum recommended for short-term use.
Why add 14 minutes?
The average person takes about 14 minutes to fall asleep. This is factored into the calculation so you wake at the optimal point.
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