Free sleep calculator: pick a wake or bedtime and see suggested bed or wake times built on 90-minute sleep cycles. A scheduling aid, not medical advice. 100% Local
How to Use the Sleep Calculator
Choose whether you are setting a wake time or a bedtime, enter the time and a maximum number of cycles, then press Calculate Times.
How it works
One sleep cycle is about 90 minutes, plus 15 minutes to fall asleep.
You get options from three cycles up to the maximum you choose.
Waking at the end of a cycle can feel easier than mid-cycle.
Features
Suggested bedtimes from a wake time, or wake times from a bedtime
Based on 90-minute sleep cycles plus fall-asleep time
Three to six cycle options
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