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Sleep Calculator
Find your ideal bedtime or wake time based on 90-minute sleep cycles. Optimize your sleep schedules to wake up feeling fresh and active.
How long does it take you to drift off?
Standard average is 14 minutes.
Sleep Science & Tips
🌙 The 90-Minute Rule: Normal human sleep cycles are composed of roughly 90 minutes of light sleep, deep sleep, and REM phases. Waking up in the middle of a sleep cycle causes grogginess (sleep inertia), whereas waking up at the end of a cycle makes you feel refreshed instantly.
🧘 4-7-8 Breathing Technique: Inhale for 4 seconds, hold your breath for 7 seconds, and exhale completely for 8 seconds. Repeating this 4 times calms your nervous system and helps you fall asleep in under 15 minutes.