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Bedtime Calculator

Find your ideal bedtime for a refreshing night sleep

Find Your Bedtime with Our Sleep Calculator

Enter your desired wake-up time and our unified sleep calculator will find the optimal bedtime based on 90-minute sleep cycles.

Calculate Bedtime

How Sleep Cycles Work

A complete sleep cycle lasts about 90 minutes. For optimal rest, aim for 5-6 full cycles (7.5-9 hours). Calculate backwards from your wake time: subtract 7.5 hours + 14 minutes to fall asleep = your ideal bedtime.

AI Insight
Waking up at the end of a sleep cycle (when sleep is lightest) helps you feel refreshed. Aim for 5-6 complete cycles (7.5-9 hours) of sleep each night for optimal health and cognitive function.

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Last updated: July 16, 2026Author: HealthFitCalc TeamCategory: SleepReviewed by Health Professionals

References

  • World Health Organization (WHO) - BMI Classification
  • National Institutes of Health (NIH) - Clinical Guidelines
  • Centers for Disease Control and Prevention (CDC) - Healthy Weight

About Bedtime Calculator

How It Works

Given a desired wake time, this calculator works backward in 90-minute sleep cycle increments to find optimal bedtimes. It accounts for the average 10-20 minutes needed to fall asleep.

How to Interpret Results

Multiple bedtimes are provided, each corresponding to completing a different number of full sleep cycles. Choosing a bedtime aligned with cycle completion helps you wake more refreshed.

Health Tips

Choose a bedtime that allows for at least 5 complete sleep cycles (7.5 hours). Stick to the same bedtime and wake time daily to regulate your circadian rhythm.

Limitations

The time to fall asleep varies by individual and night. Sleep cycle length is an average and may not match your personal pattern.

HT
HealthFitCalc TeamHealth & Fitness Editors

Last reviewed: July 16, 2026

Medical Disclaimer: This calculator is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or qualified health provider with any questions regarding your health.