Recommended Sleep Hours by Age
Health & Fitness· 18 toolsFree sleep duration calculator. Look up the CDC- and National Sleep Foundation–recommended sleep range for any age, then back-solve a bedtime to hit your target wake time. Includes 90-minute cycle alignment so you wake at the end of a REM cycle (less groggy than mid-cycle).
CDC + NSF · Sleep cycles ~90 min · Fall-asleep latency ~15 min added
Most adults: 4–6 complete cycles (6–9 hours) per night
Disclaimer: For informational purposes only. This is not medical advice — consult a qualified healthcare provider for personal recommendations.
Frequently Asked Questions
Frequently Asked Questions
References
References and sources
Related Tools
Related Tools
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