Bedtime & Sleep Cycle Calculator

Work back from your alarm in 90-minute sleep cycles.

Bedtimes (from tonight)

Sleep runs in ~90-minute cycles; waking between cycles feels far better than mid-cycle. Times include your “fall asleep” lag — go lie down at one of these and aim for 5–6 cycles (7.5–9 h).

사용 방법

  1. 모든 것은 브라우저에서 로컬로 실행됩니다. 데이터가 업로드되지 않으며 계정이 필요 없습니다.

소개

Pick your wake-up time and how long falling asleep takes you; the calculator lists bedtimes at whole sleep cycles of 7.5 and 9 hours, plus shorter options.

Waking mid-cycle groggy but at the top of a cycle refreshed is well documented — the 90-minute rhythm is the reason 6 hours can feel better than 7 hours 10 minutes.

모든 것은 브라우저에서 로컬로 실행됩니다. 데이터가 업로드되지 않으며 계정이 필요 없습니다.

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