Sleep Cycle
Calculate optimal wake-up times based on 90-minute sleep cycles so you feel refreshed instead of groggy.
Sleep Cycle
Ideal sleep or wake times based on 90-minute REM cycles
Formula & Method
Each sleep cycle ≈ 90 min; recommended 5–6 complete cycles (7.5–9 hrs); adds 14-min sleep latency
About This Calculator
Calculate optimal wake-up times based on 90-minute sleep cycles so you feel refreshed instead of groggy.
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⚕️ Medical Disclaimer
This calculator is for informational and educational purposes only. Results are estimates and may not reflect your individual health status. Always consult a qualified healthcare professional before making medical, dietary, or fitness decisions. In emergencies, call 112.