What 8–10 hours means for a 15-year-old
At 15, a child is in the National Sleep Foundation’s teenager group, which runs from 14 to 17 years. For this group the recommended amount is 8 to 10 hours of sleep in every 24 hours. Surveys regularly find that many teenagers sleep less than 8 hours on school nights.
The NSF also lists 7 hours or 11 hours as “may be appropriate”. Some healthy young people fall into these ranges, but anything outside them is not recommended. The highlighted row in the table below is the one that applies to a 15-year-old.
| Age group | Ages | Recommended | May be appropriate |
|---|---|---|---|
| Newborn | 0–3 months | 14–17 h | 11–13 or 18–19 h |
| Infant | 4–11 months | 12–15 h | 10–11 or 16–18 h |
| Toddler | 1–2 years | 11–14 h | 9–10 or 15–16 h |
| Preschooler | 3–5 years | 10–13 h | 8–9 or 14 h |
| School-age child | 6–13 years | 9–11 h | 7–8 or 12 h |
| Teenager | 14–17 years | 8–10 h | 7 or 11 h |
| Young adult | 18–25 years | 7–9 h | 6 or 10–11 h |
| Adult | 26–64 years | 7–9 h | 6 or 10 h |
| Older adult | 65+ years | 7–8 h | 5–6 or 9 h |
Asleep-by times for school mornings
The table shows when your 15-year-old needs to be asleep for 10, 9 or 8 hours, depending on when they get up.
| Wake up | 10 h sleep | 9 h sleep | 8 h sleep |
|---|---|---|---|
| 6:00 AM06:00 | 8:00 PM20:00 | 9:00 PM21:00 | 10:00 PM22:00 |
| 6:30 AM06:30 | 8:30 PM20:30 | 9:30 PM21:30 | 10:30 PM22:30 |
| 7:00 AM07:00 | 9:00 PM21:00 | 10:00 PM22:00 | 11:00 PM23:00 |
For a 7:00 AM wake-up, being asleep by 10:00 PM (22:00) gives 9 hours, the middle of the recommended range.
Can a 15-year-old catch up at weekends?
Many teenagers build up a sleep debt during the week and then sleep in late at weekends. A little extra sleep at the weekend helps, but very long lie-ins shift the body clock later. By Sunday night they can’t fall asleep, and the cycle starts again.
This mismatch between school-day and weekend sleep is sometimes called social jet lag. The fix is to get more sleep during the week, mainly by protecting the hour before bed, rather than relying on weekends to make up the difference.
Caffeine, energy drinks and screens
Coffee, cola and energy drinks are common ways for tired teenagers to get through the day, but caffeine can stay in the body for hours and make it harder to fall asleep. Energy drinks are not recommended for teenagers at all.
Screens are the other big factor. Late-night messaging and scrolling delay sleep and keep the brain alert. Agreeing on a family “devices down” time, with phones charging outside bedrooms, helps everyone, not just teenagers.
Signs a 15-year-old isn’t getting enough sleep
- Very hard to wake on school days, or sleeping several hours longer at weekends.
- Dozing in class, on the bus or in front of the TV.
- Low mood, irritability or more arguments than usual.
- Grades slipping, or finding it hard to concentrate and remember things.
If these are regular, look at how much sleep they are getting on school nights first. If your teenager snores loudly, struggles to fall asleep most nights or seems exhausted despite enough time in bed, talk to their doctor.
More answers
- How much sleep a 14-year-old needsNearby answer
- How much sleep a 16-year-old needsNearby answer
- How much sleep a 13-year-old needsNearby answer
- How much sleep a 17-year-old needsNearby answer
- Bedtime for a 4 AM wake-upRelated answer
- Bedtime for a 4:15 AM wake-upRelated answer
- Bedtime for a 4:30 AM wake-upRelated answer
- Bedtime for a 4:45 AM wake-upRelated answer
Frequently asked questions
What time should a 15-year-old go to bed?
For a 6:30 AM (06:30) wake-up, being asleep between 8:30 PM (20:30) and 10:30 PM (22:30) gives 8–10 hours. Many 15-year-olds aim for lights-out around 10:00–10:30 PM on school nights.
Is it OK for a 15-year-old to sleep until noon at weekends?
Occasionally it does no harm, but regular long lie-ins shift the body clock later and make school mornings harder. Keeping weekend wake-ups within about two hours of school days works better.
How do I know if my 15-year-old is getting enough sleep?
Signs of too little sleep include being very hard to wake, falling asleep in class or on the bus, low mood, irritability and long weekend lie-ins. If they get 8–10 hours and wake feeling rested, that is a good sign.
Related calculators
Sleep needs by age
See the recommended hours of sleep for any age, from newborns to older adults.
Bedtime calculator
Enter any wake-up time to see bedtimes that let you wake between sleep cycles.
Nap calculator
Plan a 10-, 20- or 90-minute nap and see when to set your alarm.
Sleep debt calculator
Add up the last seven nights and see how far you are from your sleep target.
Sources
- 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.
- 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;12(6):785–786. doi:10.5664/jcsm.5866.
- Centers for Disease Control and Prevention. About Sleep.
- Adolescent Sleep Working Group, Committee on Adolescence, Council on School Health. School Start Times for Adolescents. Pediatrics, 2014;134(3):642–649. doi:10.1542/peds.2014-1697.
When to seek help
Talk to your child’s doctor if they:
- snore loudly most nights, or pause, gasp or snort while asleep;
- are very hard to wake, or are often sleepy, irritable or struggling to focus during the day;
- regularly take a long time to fall asleep or wake often in the night;
- have sleep problems that are affecting school, mood or family life.