Sleep Calculator: Best Bedtime and Wake-Up Times
Plan your night around full 90-minute sleep cycles so you wake up between cycles instead of mid-deep-sleep. Pick a wake-up time to see ideal bedtimes, or a bedtime to see when to set your alarm.
How to use the sleep calculator
- Choose your mode: a wake-up time to find bedtimes, or a bedtime to find wake-up times.
- Enter the time, or tap Now to use the current time as your bedtime.
- Read the options, each one a different number of full sleep cycles, and pick the one that fits your schedule.
Examples
Wake up at 7:00 AM
Wake-up time 07:00
Go to bed around 9:46 PM, 11:16 PM, or 12:46 AM
Go to sleep at 11:00 PM
Bedtime 23:00
Wake up around 5:14 AM, 6:44 AM, or 8:14 AM
Frequently asked questions
How long is one sleep cycle?
A full sleep cycle averages about 90 minutes, moving through light sleep, deep sleep and REM. This tool plans your night in whole cycles so your alarm lands between them, not in the middle of deep sleep.
Why do the times allow extra minutes to fall asleep?
Most people take roughly 14 minutes to drift off, so the calculator adds that buffer. Your bedtimes and wake-up times are based on actual time asleep rather than the moment your head hits the pillow.
How many sleep cycles should I aim for?
Five to six cycles, about 7.5 to 9 hours, suits most adults. The tool also shows a shorter four-cycle (6 hour) option for nights when a full sleep is not possible.
Should I use the wake-up mode or the sleep mode?
Use wake-up mode when you know when your alarm must go off and want the best bedtimes. Use sleep mode when you are heading to bed now and want to know the best times to wake up.
Is this medical advice?
No. Sleep cycle length varies from person to person and night to night, so treat the results as a helpful guide rather than a medical recommendation.
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