Sleep Cycle Calculator

Suggest bed or wake times using fixed 90-minute cycles and a 15-minute sleep-onset assumption.

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Time

Calculation includes an average 15 min to fall asleep.

You should go to bed at:

05:15

1 cycles (1.5 hr)

03:45

2 cycles (3 hr)

02:15

3 cycles (4.5 hr)

00:45

4 cycles (6 hr)

23:15

5 cycles (7.5 hr) · recommended

21:45

6 cycles (9 hr) · recommended

How to Use

Assumes 90-minute cycles and 15 minutes to fall asleep; real sleep cycles vary. The model does not measure sleep quality, ensure waking refreshed or assess sleep disorders.

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