Sleep Calculator

Find your optimal sleep times. Based on 90-minute cycles. Free, private, instant.

Sleep Calculator

Optimal sleep times

Nap Calculator

Smart nap timing

Cycle Visualizer

See sleep stages

Caffeine Timer

When caffeine wears off

Sleep Debt

Track your debt

White Noise

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Sleep Diary

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Minutes to fall asleep 15 min

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Sleep Fact

"Adults who sleep less than 7 hours per night are more likely to report health problems including heart disease, asthma, and depression."

— CDC, 2023
Learn More

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Evidence-based articles to help you understand and improve your sleep.

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