clockfresh

Sleep Calculator

Plan bedtimes and wake-up times around estimated sleep cycles.

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Sleep cycles --:--

Choose a wake-up time or bedtime to calculate cycle-friendly options.

6 cycles A longer sleep window for many adults.
--:-- Set alarm
5 cycles A common planning target.
--:-- Set alarm
4 cycles A shorter sleep window.
--:-- Set alarm
3 cycles Short sleep; use only when your schedule leaves no better option.
--:-- Set alarm

How it works

Choose a wake-up time to see suggested bedtimes, or choose a bedtime to see possible wake-up times. The calculator includes a fall-asleep buffer before the first estimated sleep cycle. Sleep needs vary; adults generally need at least 7 hours, and persistent sleep problems are a reason to talk with a qualified health professional.

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Questions

Why 90-minute cycles?
Sleep cycles vary, but 90 minutes is a common planning shortcut. Medical sources describe typical cycles around 80–100 minutes, so treat these results as estimates.
Can I send a result to the alarm clock?
Yes. Each wake-up result links directly to the Clockfresh alarm clock with the time prefilled.
Is this medical advice?
No. It is a planning helper, not medical guidance.

Sources checked