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Sleep Cycle & Bedtime Calculator

Wake Up Energized with 90-Minute REM Cycles
15 Minutes
Suggested Sleep Times
Best Bedtimes to Wake Up at 7:00 AM
11:45 PM
Optimal: 6 Sleep Cycles (7.5 Hours)
Completing 5 or 6 full sleep cycles (7.5 to 9 hrs) ensures maximum REM dreaming & physical restoration.

Frequently Asked Questions

Human sleep progresses in 90-minute cycles through Light Sleep (NREM 1 & 2), Deep Slow-Wave Sleep (NREM 3), and REM (Dreaming). Waking up in the middle of deep sleep causes sleep inertia (grogginess and brain fog). Waking at the end of a 90-minute cycle leaves you feeling refreshed and alert.

Sleep science research shows the average adult takes approximately 14 to 15 minutes to fall asleep after turning off the lights.