How long is a REM cycle?

A standard sleep cycle lasts about 90 minutes.

REM Sleep Cycle & Bedtime Clock

Calculate optimal bedtime and wake-up times based on 90-minute REM sleep cycles and sleep onset latency.

Configuration

Target Wake-up Time

Sleep Onset Latency (Time it takes to fall asleep)

Optimal Bedtimes

Based on 15 mins latency + 90 min cycles

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