Working back from a 5:00 AM alarm
Sleep moves through cycles that last about 90 minutes. Counting back from 5:00 AM in whole cycles, then adding 15 minutes to fall asleep, gives three bedtimes that let your alarm go off near the end of a cycle:
- Six cycles (9 hours): asleep by 8:00 PM, so in bed by 7:45 PM (19:45).
- Five cycles (7.5 hours): asleep by 9:30 PM, so in bed by 9:15 PM (21:15).
- Four cycles (6 hours): asleep by 11:00 PM, so in bed by 10:45 PM (22:45).
Waking at the end of a cycle, when sleep is lighter, usually feels easier than being pulled out of deep sleep halfway through one.
Which 5 AM bedtime should you choose?
9:15 PM is the realistic target for most adults. It gives 7.5 hours of sleep, which meets the recommendation that adults get at least 7 hours a night.
7:45 PM gives 9 hours. It suits teenagers with very early starts and people whose shifts are physically hard, but it is early enough to clash with family meals and evening plans, so few adults can keep it up.
10:45 PM leaves only 6 hours. It is fine for an odd night, but a 5:00 AM alarm on 6 hours of sleep, day after day, tends to catch up with you.
If you take more or less than 15 minutes to fall asleep
The times above assume 15 minutes to fall asleep. If you usually drop off faster or lie awake longer, move your bedtime by the difference. The highlighted row matches the answer at the top of this page.
| Fall asleep in | 9 h | 7.5 h | 6 h |
|---|---|---|---|
| 5 min | 7:55 PM19:55 | 9:25 PM21:25 | 10:55 PM22:55 |
| 10 min | 7:50 PM19:50 | 9:20 PM21:20 | 10:50 PM22:50 |
| 15 min | 7:45 PM19:45 | 9:15 PM21:15 | 10:45 PM22:45 |
| 20 min | 7:40 PM19:40 | 9:10 PM21:10 | 10:40 PM22:40 |
| 30 min | 7:30 PM19:30 | 9:00 PM21:00 | 10:30 PM22:30 |
Going to bed while it’s still light outside
With a 5:00 AM alarm, bedtime can come before sunset in summer, and the mornings are dark for much of the year. Blackout curtains or an eye mask make an early bedtime easier, and a cool, quiet bedroom helps too. Dim the lights and put screens away for the last half hour before bed.
In the morning, bright light soon after waking helps your body clock accept the early start. Open the curtains, switch on the main lights, or step outside once it’s light. Keeping the same wake-up time on days off, or within about an hour of it, makes the weekday alarm far easier to face.
More answers
- Bedtime for a 4:45 AM wake-upNearby answer
- Bedtime for a 5:15 AM wake-upNearby answer
- Bedtime for a 4:30 AM wake-upNearby answer
- Bedtime for a 5:30 AM wake-upNearby answer
- Wake-up time if you sleep at 8 PMRelated answer
- Wake-up time if you sleep at 8:30 PMRelated answer
- Wake-up time if you sleep at 9 PMRelated answer
- Wake-up time if you sleep at 9:30 PMRelated answer
Frequently asked questions
Is 9:15 PM too early for a 5 AM alarm?
No. Allowing 15 minutes to fall asleep, a 9:15 PM (21:15) bedtime gives five full cycles, or 7.5 hours of sleep, before a 5:00 AM alarm. Going to bed later means less than 7.5 hours.
How much sleep do I get if I go to bed at 10 PM and wake at 5 AM?
About 6 hours 45 minutes, if you fall asleep by 10:15 PM. That ends partway through a cycle. See wake-up times if you sleep at 10 PM for times that line up better.
Should I nap if I wake up at 5 AM?
A short nap of 10–20 minutes in the early afternoon can help on a long day. Keep it short and not too late, so it doesn’t make your 9:15 PM bedtime harder. The nap calculator shows good wake-up times.
Related calculators
Bedtime calculator
Enter any wake-up time to see bedtimes that let you wake between sleep cycles.
Wake-up time calculator
Going to bed now or at a set time? Find wake-up times that land at the end of a cycle.
Sleep needs by age
See the recommended hours of sleep for any age, from newborns to older adults.
Sleep debt calculator
Add up the last seven nights and see how far you are from your sleep target.
Sources
- National Institute of Neurological Disorders and Stroke. Brain Basics: Understanding Sleep.
- Watson NF, et al. Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society. Journal of Clinical Sleep Medicine, 2015;11(6):591–592. doi:10.5664/jcsm.4758.
- Hirshkowitz M, et al. National Sleep Foundation’s sleep time duration recommendations: methodology and results summary. Sleep Health, 2015;1(1):40–43. doi:10.1016/j.sleh.2014.12.010.
- Centers for Disease Control and Prevention. About Sleep.
When to seek help
Talk to a doctor if you:
- regularly take longer than 30 minutes to fall asleep, or wake in the night and can’t get back to sleep;
- snore loudly, or someone notices you gasp or stop breathing while asleep;
- feel very sleepy during the day, especially while driving or working, despite enough time in bed.