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Wake-up time calculator

Pick the time you need to be up. You get bedtimes that end on a full sleep cycle, so your alarm doesn't catch you in deep sleep.

Wake-up time · tap it to type, or step by 15 minutes

Go to bed at

10:45PM

5 full cycles, 7 h 30 min asleep · best fit for most adults

If that doesn't work

9:15 PM 6 cycles, 9 hThe most rest

12:15 AM 4 cycles, 6 hA short night

1:45 AM 3 cycles, 4 h 30 minOnly if you must

Every bedtime includes about 15 minutes to fall asleep.

90-minute sleep cycles: The average length of one cycle of light, deep and dream sleep.
15 minutes to fall asleep: Added to every bedtime. You can change it.
Runs in your browser: Nothing to install, and nothing you type is saved.

Bedtime sorted

Now make sure you get up at 6:30.

Bed Quitter is an alarm that keeps ringing until you get out of bed and move. You pick one of seven moves, your phone's camera counts a few reps, and no photo or video from the camera leaves your phone.

A woman stretching her arms overhead beside a sunny window, up and out of bed.

How the calculator works

Sleep runs in cycles of light, deep and dream sleep, and one cycle lasts about 90 minutes. Waking at the end of a cycle, when sleep is light, usually feels easier than being pulled out of deep sleep.

So the calculator counts back from your wake-up time in 90-minute steps, then takes off 15 minutes, about how long most people need to fall asleep. Real cycles run from about 70 to 120 minutes, so treat these times as a starting point and nudge them by a few minutes.

How many cycles do you need?

Cycles	Time asleep	Good for
6	9 h	Catching up after short nights
5	7 h 30 min	Most adults, most nights
4	6 h	A short night, now and then
3	4 h 30 min	Only when there's no other choice

Most adults need at least 7 hours a night, so 5 or 6 cycles is the usual aim.

Why waking mid-cycle feels so bad

Waking from deep sleep brings sleep inertia: the heavy, foggy feeling that can hang around for half an hour or more. It's why snooze feels so tempting and rarely helps. Each snooze starts light sleep you don't get to finish.

Bedtimes for common wake-up times

Questions people ask

What time should I go to bed to wake up at 6 AM?

Go to bed at 10:15 PM for 5 full cycles, or 8:45 PM for 6. Both include about 15 minutes to fall asleep.

Is 6 hours of sleep enough?

For most adults, no. Health guidelines recommend at least 7 hours a night. Six hours, 4 full cycles, is fine once in a while, but short nights add up.

Why am I tired after 8 hours of sleep?

Eight hours rarely lines up with whole cycles, so your alarm may catch you partway through one. Late caffeine, alcohol and an irregular schedule can also leave you tired. If you're worn out most days, talk to a doctor.

Does hitting snooze give me more rest?

Not really. The minutes between snoozes are light, broken sleep, and they can leave you groggier. Setting the alarm for when you actually need to get up works better.

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