Free Sleep Cycle & Optimal Wake Time Calculator Online
Calculate ideal bedtimes and wake times based on natural 90-minute REM sleep cycles to wake up feeling refreshed and avoid grogginess. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Choose Goal
Select 'I need to wake up at...' or 'If I go to bed now...'.
Enter Target Time
Specify desired wake-up alarm time.
View Sleep Cycles
Review optimal bedtimes for 5 cycles (7.5 hours) or 6 cycles (9.0 hours).
Frequently Asked Questions
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