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Sleep by Age · Young adult

How much sleep at age 18?

The National Sleep Foundation recommends 79 hours for young adults. 611 hours may be appropriate depending on individual variation.

Recommended
79h
May be OK
611h
Typical cycles
5
Age group
Young adult
Developmental Notes

Young adults (ages 18–25) still retain some of the adolescent circadian delay, but adult sleep architecture is largely in place. Social jetlag — the mismatch between workday and free-day sleep timing — tends to peak in this age range and correlates with worse metabolic and mental health outcomes.

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Frequently Asked

Questions & answers.

How many hours of sleep does a 18-year-old need?

The National Sleep Foundation recommends 7–9 hours per night for young adults. 6–11 hours may be appropriate for individual variation.

Is 7 hours enough sleep at age 18?

7 hours is the floor of the recommended range — sufficient for most young adults on a consistent schedule, but below the middle of the NSF range. If you feel tired at this duration, try adding 30 minutes for a week.

What is the best bedtime for a 18-year-old?

Bedtime depends on wake time, not age alone. Most young adults need 5 complete sleep cycles (~450 minutes, though personal cycle length varies from 75–115 min). Count backwards from the intended wake time to set a cycle-aligned bedtime.

Why do young adults need 7–9 hours of sleep?

Young adults (ages 18–25) still retain some of the adolescent circadian delay, but adult sleep architecture is largely in place. Social jetlag — the mismatch between workday and free-day sleep timing — tends to peak in this age range and correlates with worse metabolic and mental health outcomes.

Does a 18-year-old need naps?

Naps are optional at this age. A 20-minute power nap can be a useful recovery tool, but is not required.

Nearby ages

Based on NSF (Hirshkowitz et al., 2015) sleep duration recommendations