Sleep Cycle Calculator

NREM Stage 1: Very light sleep, easily woken. Transition between wakefulness and sleep.
NREM Stage 2: Deeper sleep, heart rate slows, body temperature drops. Most of your total sleep time is spent here.
NREM Stage 3: Deep sleep (slow-wave sleep). Crucial for physical restoration, growth hormone release, and feeling refreshed. Hardest stage to wake from.
REM Sleep: Brain activity increases, similar to being awake. Characterized by rapid eye movements, vivid dreaming, and temporary muscle paralysis. Important for cognitive functions like memory consolidation and learning.

Find the best times to wake up or go to sleep based on natural sleep cycles.

Calculate Your Optimal Sleep Times

I want to calculate my... Bedtime Wake-up Time

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Calculate wake-up times if you go to bed now:

Disclaimer: This calculator uses average sleep cycle lengths (approx. 90 minutes) and an estimated time to fall asleep (15 minutes). Individual sleep cycles and the time it takes to fall asleep can vary. This tool provides suggestions, not medical advice. Factors like sleep quality, interruptions, stress, and health conditions significantly impact how rested you feel. Consult a doctor for persistent sleep issues.