Sleep Calculator: What Time Should I Go to Bed?

Waking up in the middle of a sleep cycle is one reason you can feel groggy even after a full night in bed. This free sleep calculator works out the best times to go to bed or wake up, so you’re more likely to wake at the end of a cycle.

Pick your wake-up time to see when to go to bed, or pick your bedtime to see when to set your alarm. You can also tap “Going to bed now.”

Sleep Calculator

Find the best time to go to bed or wake up, based on 90-minute sleep cycles.

Based on an average 90-minute sleep cycle. Real cycles vary from about 70 to 120 minutes, so treat these as a guide. Most adults need 7 to 9 hours of sleep.

How the Sleep Calculator Works

During the night, your brain moves through repeating sleep cycles. Each cycle includes lighter sleep, deep sleep, and REM (dreaming) sleep, and lasts about 90 minutes on average, though it can range from roughly 70 to 120 minutes.

The calculator:

  1. Takes your wake-up time or bedtime
  2. Adds the time it usually takes you to fall asleep (15 minutes by default)
  3. Counts in 90-minute cycles to suggest times that line up with the end of a cycle

Five or six cycles (7.5 or 9 hours) are marked as the best options, because most adults need 7 to 9 hours of sleep.

How Much Sleep Do You Need?

AgeRecommended sleep
18 to 607 or more hours a night
61 to 647 to 9 hours
65 and older7 to 8 hours

Source: CDC. Needs vary from person to person. If you wake up refreshed and stay alert during the day, you're likely getting enough.

Bedtime Chart: What Time Should I Go to Bed?

Based on 5 or 6 sleep cycles plus 15 minutes to fall asleep:

Wake-up timeBedtime for 7.5 hrs (5 cycles)Bedtime for 9 hrs (6 cycles)
5:00 AM9:15 PM7:45 PM
5:30 AM9:45 PM8:15 PM
6:00 AM10:15 PM8:45 PM
6:30 AM10:45 PM9:15 PM
7:00 AM11:15 PM9:45 PM
7:30 AM11:45 PM10:15 PM
8:00 AM12:15 AM10:45 PM

Why Sleep Changes After 40

Many women notice their sleep changes in their 40s and 50s. During perimenopause and menopause, hot flashes and night sweats can wake you up, and shifting hormone levels can make it harder to stay asleep. Waking around 3 or 4am and struggling to drop back off is very common.

If that sounds familiar, read why you wake up at 3am every night, or take our free perimenopause quiz to see how your symptoms line up. For night sweats, see our guide to hot flashes and what helps.

Tips for Better Sleep

  • Keep the same wake-up time every day, including weekends. This helps more than a fixed bedtime.
  • Keep your bedroom cool, dark and quiet. A cool room helps with night sweats.
  • Cut off caffeine by early afternoon. It can stay in your system for hours.
  • Limit alcohol in the evening. It can make you sleepy at first but disrupts sleep later in the night.
  • Get daylight in the morning and stay active during the day.
  • Put screens away 30 to 60 minutes before bed.
  • If you can't sleep after about 20 minutes, get up and do something calm in dim light, then go back to bed when you feel sleepy.

When to See a Doctor

Talk to a doctor if:

  • You have trouble sleeping at least 3 nights a week for 3 months or more
  • You snore loudly, or someone notices you stop breathing or gasp during sleep. Sleep apnea becomes more common in women after menopause.
  • You feel very sleepy during the day, or nod off while driving
  • Night sweats, low mood or anxiety are keeping you awake

Frequently Asked Questions

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

Around 10:15pm for 7.5 hours of sleep, or 8:45pm for 9 hours. These times include 15 minutes to fall asleep.

How long is one sleep cycle?

About 90 minutes on average, but it varies from about 70 to 120 minutes between people and through the night.

Is it better to sleep 6 hours or 7.5 hours?

Most adults need at least 7 hours. Waking at the end of a cycle may help you feel less groggy, but getting enough total sleep matters more.

Why do I wake up at 3am?

It's common, especially during perimenopause, and can be linked to night sweats, stress, alcohol, or needing the bathroom. See why you wake up at 3am.

Is this sleep calculator accurate?

It's a helpful guide, not an exact measurement. Everyone's cycles are a little different, so try the suggested times for a week and adjust.

Does it save my information?

No. Nothing is saved or sent anywhere.

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This calculator is for general wellness information only and is not medical advice. Read our Medical Disclaimer and Editorial Policy.

Sources

Health note: Content on this site is for general information only and is not medical advice. Always consult your doctor about health concerns.

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