SleepCycleHub

Wake-up calculator: what time should I wake up?

Enter your bedtime — or tap "Sleep now" — and set your alarm for the end of a sleep cycle instead of a random point in the middle of one.

Calculator

If I go to sleep now

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Fine-tune: 15 min to fall asleep · 90-min cycles

Most adults take 10–20 minutes to fall asleep. Cycles vary between about 80 and 110 minutes across people and across the night; 90 is the average.

Heading to bed right now? Wake up at one of these times:

Shortcuts: W wake-up mode, B bedtime mode, N sleep now, 1–4 pick a result.

Wake-up times for common bedtimes

Includes 15 minutes to fall asleep. The highlighted column gives five full cycles.

Wake-up times for bedtimes from 9:00 pm to 1:30 am
Bedtime6 cycles (9 h)5 cycles (7.5 h)4 cycles (6 h)
9:00 pm6:15 am4:45 am3:15 am
9:30 pm6:45 am5:15 am3:45 am
10:00 pm7:15 am5:45 am4:15 am
10:30 pm7:45 am6:15 am4:45 am
11:00 pm8:15 am6:45 am5:15 am
11:30 pm8:45 am7:15 am5:45 am
12:00 am9:15 am7:45 am6:15 am
12:30 am9:45 am8:15 am6:45 am
1:00 am10:15 am8:45 am7:15 am
1:30 am10:45 am9:15 am7:45 am

Why the exact minute matters less than you'd think

The rule of thumb is solid: waking in lighter sleep generally feels better than being dragged out of deep slow-wave sleep. But cycle length drifts by 10–20 minutes over a night, so treat the time as a window.

If you often wake up a few minutes before the alarm feeling fine, that's your natural cycle boundary — try nudging the cycle-length slider down. If the alarm keeps catching you groggy, try nudging it up.

Making the first ten minutes easier

  • Get light fast. Open the curtains or step outside. Morning light is the strongest signal for setting your body clock.
  • Skip the snooze. Snoozing fragments the last light sleep of the night. Set the alarm for the time you'll actually get up.
  • Give grogginess 15–30 minutes. Some sleep inertia is normal even at the right time; it usually clears within half an hour.
  • Consistently exhausted despite enough hours? That's worth raising with a doctor — conditions like sleep apnea fragment sleep without you noticing.

Questions people ask

If I go to bed at 11 pm, when should I wake up?

With 15 minutes to fall asleep: 6:45 am gives five full cycles (7.5 hours) and 8:15 am gives six (9 hours). 5:15 am is four cycles.

If I fall asleep at midnight, what time should I wake up?

If you are actually asleep at midnight, 7:30 am is five cycles and 9:00 am is six. If midnight is when you get into bed, add your usual time to fall asleep.

Why do I feel worse after 8 hours than after 7.5?

Eight hours can end partway through a cycle, while 7.5 hours ends near a boundary. Cycle length varies, though, so this does not happen to everyone every night.

Do sleep-tracking alarms do the same thing?

Smart alarms estimate light sleep from movement or heart rate and ring within a window. This calculator does the same job with arithmetic — no wearable needed.