Free sleep calculator

What time should I wake up if I go to bed at 8:30 pm?

If you go to bed at 8:30 pm, wake up at 2:45 am (6 hours of sleep), 4:15 am (7.5 hours), or 5:45 am (9 hours). Each time allows 15 minutes to fall asleep and ends on a full 90-minute sleep cycle. Most adults need at least 7 hours, so 4:15 am or 5:45 am is the better target.

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Wake-up times after an 8:30 pm bedtime

  • 2:45 am

    6 hours · 4 cycles

    Short night

  • 4:15 am

    7.5 hours · 5 cycles

    Recommended

  • 5:45 am

    9 hours · 6 cycles

    Recommended

Adults aged 18 to 60 years need 7 or more hours of sleep, according to the CDC. Times include 15 minutes to fall asleep.

If it takes you longer to fall asleep

Plan to wake up a little later. If you usually need 30 minutes to fall asleep after an 8:30 pm bedtime, wake up at 3:00 am, 4:30 am, or 6:00 am instead.

Wake-up times after an 8:30 pm bedtime by time to fall asleep
Time to fall asleep6 hours (4 cycles)7.5 hours (5 cycles)9 hours (6 cycles)
5 minutes2:35 am4:05 am5:35 am
15 minutes2:45 am4:15 am5:45 am
30 minutes3:00 am4:30 am6:00 am

Wake-up times for teens and children

Teens need 8 to 10 hours of sleep, so after an 8:30 pm bedtime, a teen should sleep until 5:45 am. Children aged 6 to 12 need 9 to 12 hours, so they should sleep until at least 5:45 am. If school starts earlier than that, move bedtime earlier.

Other bedtimes

Going to bed earlier? See wake-up times for 8:00 pm. Going to bed later? See wake-up times for 9:00 pm. Need to wake up at a set time instead? See bedtimes for common wake-up times.

For wind-down routines and breathing exercises before bed, see our sleep resources.

Frequently asked questions

What time should I wake up if I go to bed at 8:30 pm?

If you go to bed at 8:30 pm, wake up at 2:45 am (6 hours of sleep), 4:15 am (7.5 hours), or 5:45 am (9 hours). Each time allows 15 minutes to fall asleep and ends on a full 90-minute sleep cycle. Most adults need at least 7 hours, so 4:15 am or 5:45 am is the better target.

How long will I sleep if I go to bed at 8:30 pm and wake up at 4:15 am?

About 7.5 hours, which is five 90-minute sleep cycles, after roughly 15 minutes to fall asleep.

Sources

  1. Centers for Disease Control and Prevention. About Sleep: recommended hours of sleep by age.
  2. 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. Sleep, 2015.
  3. Paruthi S, et al. Recommended amount of sleep for pediatric populations: a consensus statement of the American Academy of Sleep Medicine. Journal of Clinical Sleep Medicine, 2016.
  4. Ohayon M, et al. National Sleep Foundation's sleep quality recommendations: first report. Sleep Health, 2017.
  5. Patel AK, et al. Physiology, Sleep Stages. StatPearls, NCBI Bookshelf.

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