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Sleep Calculators
Find when to go to bed or wake up in whole sleep cycles, see how long you slept, and add up the sleep you are missing over a week.
Nothing you enter leaves your device.
Results are estimates for general information only, not medical advice.
All sleep tools
Good to know
Frequently asked questions
How much sleep do adults need?
Seven hours or more a night, according to the American Academy of Sleep Medicine and the Sleep Research Society.
When should I see a doctor about sleep?
If you are often tired despite enough sleep, snore loudly or have slept badly for weeks.
Are these calculators medical advice?
No. They give estimates for general information, using the published formulas named on each page. For decisions about your health, talk to a doctor or another qualified professional.
Is anything I enter stored or sent?
No. Every calculator runs in your browser. Nothing you type is saved, sent to a server or used for advertising.
Can I use these calculators on a phone?
Yes. Every calculator works in a phone browser, with metric or imperial units where it applies, and with the number format of your language.