The best time to wake up is 7 hours 45 minutes after you get into bed: that's 15 minutes to fall asleep plus 5 full 90-minute sleep cycles (7.5 hours). Going to bed at 11 PM, for example, points to a 6:45 AM alarm.
Find your bedtime in the chart below and read across. Every wake-up time already includes 15 minutes to fall asleep.
Free toolSleep CalculatorBest bedtime or wake-up time, based on 90-minute sleep cycles.Wake-up time chart by bedtime
| Bedtime | 4 cycles (6 h) | 5 cycles (7.5 h) | 6 cycles (9 h) |
|---|---|---|---|
| 8:00 PM | 2:15 AM | 3:45 AM | 5:15 AM |
| 8:30 PM | 2:45 AM | 4:15 AM | 5:45 AM |
| 9:00 PM | 3:15 AM | 4:45 AM | 6:15 AM |
| 9:30 PM | 3:45 AM | 5:15 AM | 6:45 AM |
| 10:00 PM | 4:15 AM | 5:45 AM | 7:15 AM |
| 10:30 PM | 4:45 AM | 6:15 AM | 7:45 AM |
| 11:00 PM | 5:15 AM | 6:45 AM | 8:15 AM |
| 11:30 PM | 5:45 AM | 7:15 AM | 8:45 AM |
| 12:00 AM | 6:15 AM | 7:45 AM | 9:15 AM |
| 12:30 AM | 6:45 AM | 8:15 AM | 9:45 AM |
| 1:00 AM | 7:15 AM | 8:45 AM | 10:15 AM |
| 1:30 AM | 7:45 AM | 9:15 AM | 10:45 AM |
| 2:00 AM | 8:15 AM | 9:45 AM | 11:15 AM |
Going to bed at a time that isn't listed, or right now? The sleep calculator gives wake-up times from any bedtime, including "if I go to sleep now."
How to read the chart
- 5 cycles (7.5 hours) is the everyday target for most adults. It sits inside the 7-to-9-hour range that sleep experts recommend.
- 6 cycles (9 hours) suits recovery nights, heavy training weeks, illness or anyone who naturally needs more. Teens often do.
- 4 cycles (6 hours) is a short night. It ends on a cycle, so you may wake up feeling OK, but it doesn't give most adults enough sleep. Several in a row builds sleep debt.
The math behind every row is the same: bedtime + 15 minutes + (cycles × 90 minutes).
Why wake up at the end of a cycle?
Each night you move through light sleep, deep sleep and REM sleep in loops of about 90 minutes. Toward the end of each loop, sleep gets lighter. An alarm that goes off then tends to feel much easier than one that drags you out of deep sleep, which can leave you groggy for a while.
That's why 7.5 hours can sometimes feel better than 8. The extra 30 minutes may put your alarm in the middle of a new cycle.
Your real cycles aren't exactly 90 minutes
Ninety minutes is an average. Cycles run roughly 70 to 120 minutes, and they change across the night. Your time to fall asleep also varies with stress, caffeine and how tired you are. So treat the chart as a strong starting point, then fine-tune:
- Pick the chart time for your usual bedtime.
- Use it for 5 to 7 days and notice how you feel in the first 15 minutes after waking.
- If you're groggy, try an alarm 15 minutes earlier or later for another few days.
- Keep whatever feels best and hold it steady, weekends included.
Waking up before the alarm
If you often wake 10 to 20 minutes before your alarm, that may be your body finishing a cycle on its own. If you feel alert, getting up is usually better than trying to doze back off for a few minutes. If you're waking hours early and can't get back to sleep, that's different, and worth reading about in lying in bed awake.
Should you set your wake-up time or your bedtime first?
If you can, choose your wake-up time first and build bedtime around it. A consistent wake-up time is one of the strongest signals for your body clock, and it's the one you can actually control: you can't force yourself to fall asleep, but you can get up. Once it's fixed, use the bedtime chart by wake-up time to set your target for going to bed.
Use this wake-up chart for the other situations: when bedtime is already fixed or late, and you want to know when to set the alarm.
Make the alarm work for you
- Set one alarm, not three. Repeated snoozing chops your last, lightest stretch of sleep into pieces. How to stop hitting snooze.
- Get light right away. Open the curtains or switch on bright lights as soon as you're up.
- Give it 15 to 30 minutes. Some morning grogginess is normal even when you wake at the perfect time.