How much sleep do I need?
Last reviewed: 14 September 2026
Adults need 7 to 9 hours. That is the short answer, and it is right for most people — but the range exists for a reason, and there is a simple test that tells you where in it you sit.
How much sleep do you need?
Pick an age and get the recommended range, plus the bedtime for the morning you have to make.
Recommended hours of sleep by age
These are the figures the major sleep bodies agree on. They are ranges rather than targets because healthy people genuinely differ by an hour or more in either direction — what matters is where you sit inside the range, not hitting the midpoint.
| Age | Recommended sleep | Notes |
|---|---|---|
| Newborn (0–3 months) | 14–17 hours | Spread across the whole 24 hours, in short stretches. |
| Infant (4–11 months) | 12–15 hours | Including naps. Night sleep starts consolidating from around 4 months. |
| Toddler (1–2 years) | 11–14 hours | Including naps. Two naps usually become one during this period. |
| Preschool (3–5 years) | 10–13 hours | Including naps, which most children drop somewhere in this band. |
| School age (6–13 years) | 9–12 hours | The AASM gives 9–12; the National Sleep Foundation gives 9–11. |
| Teenager (14–17 years) | 8–10 hours | More than adults need. The body clock shifts later during puberty. |
| Adult (18–64 years) | 7–9 hours | The AASM advises 7 or more hours on a regular basis. |
| Older adult (65+) | 7–8 hours | The need barely drops; sleep becomes lighter and more broken. |
Adults need 7 to 9 hours. Teenagers need more than adults, not less — 8 to 10 hours. The belief that sleep need falls sharply through the teenage years and again in old age is one of the most persistent myths about sleep, and it is wrong in both directions.
How to find your own number
The range is a population statistic. Your personal requirement is a specific number, and you can measure it in about a week.
Take a stretch with nothing to get up for — a holiday, or a run of days off. Go to bed when you feel sleepy, and get up without an alarm. For the first two or three days you will probably sleep unusually long, because you are repaying accumulated debt. After that your sleep length will settle. The settled number is your requirement.
Two things make this test go wrong. Drinking alcohol during the week distorts it, because alcohol fragments the second half of the night and makes sleep less efficient. And staying up far later than usual because you are on holiday shifts your body clock, which changes how long you sleep. Keep the bedtime roughly normal and let the wake-up float.
Signs you are not getting enough
The awkward part of sleep deprivation is that it degrades the faculty you would use to notice it. In controlled studies, people restricted to six hours a night reported that their sleepiness stopped getting worse after two or three days, while their measured reaction times kept deteriorating for the full two weeks. Feeling fine is weak evidence.
These are better indicators:
- You need an alarm every day. Someone sleeping enough usually wakes within about twenty minutes of it on most days.
- You sleep much longer at weekends. A lie-in of more than an hour past your weekday wake-up is repayment, and it points straight at the weekday total.
- You fall asleep in under five minutes. That reads as a sign of good sleep and is usually the opposite — it indicates high sleep pressure. Fifteen to twenty minutes is normal.
- You are sleepy in a warm room, in a meeting, or after lunch. A well-rested person gets bored in those situations; a sleep-deprived one falls asleep.
- You rely on caffeine to start. Enjoying coffee is one thing; needing it to become functional is a different signal.
Quantity is not the whole story
Eight hours in bed is not eight hours of sleep, and eight hours of broken sleep is not equivalent to eight hours of consolidated sleep. If you are inside the recommended range and still tired, the limiting factor is usually one of these:
- Continuity. Frequent brief arousals fragment the architecture without properly waking you. You will not remember them.
- Timing. Sleeping 11:00 PM to 7:00 AM on weekdays and 2:00 AM to 10:00 AM at weekends is a permanent mild jet lag, even though both are eight hours.
- Alcohol. It shortens sleep latency and then suppresses REM and breaks up the second half of the night.
- Undiagnosed sleep apnoea. The commonest missed cause of unrefreshing sleep in adults. Loud snoring, witnessed breathing pauses, waking with a dry mouth or headache, and daytime sleepiness despite adequate hours is the pattern to take to a GP or doctor.
Children and teenagers
Children need substantially more sleep than adults, and the requirement falls slowly rather than in steps. The commonest mistake is assuming that starting school reduces how much sleep a child needs — it does not; it just makes the morning non-negotiable, which means the adjustment has to happen at the bedtime end.
Teenagers are the group with the largest gap between need and reality. During puberty the circadian clock shifts one to two hours later, so a 15-year-old who is wide awake at 11:00 PM is not being difficult — melatonin release has genuinely moved. Because school start times have not moved with it, most teenagers accumulate a substantial deficit across a term. Morning daylight and a consistent wake-up time do more to correct this than an earlier bedtime, which usually just produces a teenager lying awake in the dark.
Sources. Age-based recommendations are from the National Sleep Foundation’s sleep duration recommendations and the American Academy of Sleep Medicine’s consensus statements on sleep for healthy children and for adults. Sleep stage figures are from published polysomnography data. This page is general wellbeing information, not medical advice — speak to a GP or doctor about persistent sleep problems.
Common questions
How many hours of sleep do I need?
If you are an adult aged 18 to 64, 7 to 9 hours a night. The American Academy of Sleep Medicine recommends 7 or more hours on a regular basis. Teenagers need 8 to 10 hours, school-age children 9 to 12, and adults over 65 need 7 to 8.
How much sleep does an adult need?
7 to 9 hours a night for adults aged 18 to 64. Seven is the floor rather than the target — it leaves no margin for a late night or a bad one.
How many hours of sleep do adults need?
Seven to nine hours a night for adults aged 18 to 64. The American Academy of Sleep Medicine puts it as 7 or more hours on a regular basis, and the National Sleep Foundation gives the 7 to 9 hour range.
How much sleep should I get a night?
If you are an adult, seven to nine hours. Where you sit inside that range is individual — the test described above, sleeping without an alarm for a week, is how you find your own number rather than the population average.
Do older adults need less sleep?
Only slightly: the recommendation drops from 7–9 hours to 7–8 from age 65. What changes much more is the structure of sleep — it becomes lighter and more fragmented, and there is less deep sleep — which is often misread as needing less.
Is it true that some people only need 4 hours of sleep?
A very small number of people carry rare genetic variants associated with naturally short sleep, but they are well under 1% of the population. Most people who believe they are short sleepers catch up substantially at weekends, which is the giveaway that they are not.
How much sleep do I need by age?
Newborns 14–17 hours, infants 12–15, toddlers 11–14, preschoolers 10–13, school-age children 9–12, teenagers 8–10, adults 7–9, and adults over 65 7–8 hours.
Why am I still tired after 8 hours of sleep?
Usually quality rather than quantity: fragmented sleep, irregular timing, alcohol, or undiagnosed sleep apnoea. Grogginess in the first 20 to 30 minutes after waking is normal sleep inertia. Persistent tiredness on adequate sleep is worth taking to a GP or doctor.