How Much Sleep Do I Need
The published ranges by age, what counts toward the total, and the signs that you are under your own number.
Recommended hours by age
These ranges come from the American Academy of Sleep Medicine and the Sleep Foundation, and they are the figures most paediatric and primary-care guidance repeats. They describe a population, not an individual.
| Age | Hours per 24 h | Notes |
|---|---|---|
| 0–3 months | 14–17 | Including naps; no settled schedule yet |
| 4–11 months | 12–16 | Including naps |
| 1–2 years | 11–14 | Including naps |
| 3–5 years | 10–13 | Including naps; naps usually end around 4–5 |
| 6–12 years | 9–12 | School-age; weekends rarely make up a weekday debt |
| 13–18 years | 8–10 | Circadian phase shifts later at puberty |
| 18–64 years | 7–9 | Most adults need 7.5–8.5 to feel rested |
| 65+ | 7–8 | Sleep gets lighter and more fragmented; total need drops slightly |
"Per 24 hours" matters: a two-year-old who sleeps 10 hours at night and 2 at midday is inside the range. An adult who sleeps 5 hours on weekdays and 10 at the weekend averages 6.4, which is not the same as sleeping 8 every night.
Signs you are under your own number
- Falling asleep within five minutes of lying down — usually a sign of insufficient sleep, not good sleep hygiene.
- Needing an alarm to wake every day, and sleeping much later on free days (a "social jet lag" of two hours or more).
- Daytime sleepiness that shows up in meetings, on public transport or while driving.
- Irritability, poor concentration and appetite changes that improve after a longer night.
Driving while drowsy is the risk worth taking seriously: after 17–19 hours awake, reaction times resemble those at a blood-alcohol level above the legal limit in most countries.
Sleep debt is not a bank account
You cannot fully repay a week of short nights with one long lie-in. Recovery sleep restores alertness first and cognitive performance more slowly, and it does not undo the metabolic effects of the short week. The practical rule: keep the wake time within about an hour of usual, seven days a week, and let bedtime drift earlier rather than later.
Quality counts as much as quantity. Eight hours of fragmented sleep with frequent waking is not the same as eight hours of consolidated sleep. If you are in bed long enough but still tired, the useful question is why you wake, not how to add another hour.
See a clinician rather than a calculator if you snore loudly with pauses, wake gasping, have morning headaches, or fall asleep unintentionally during the day. Those point at sleep apnoea and other conditions that a bedtime schedule cannot fix. Nothing on this page is medical advice.
Questions
Can I train myself to need less sleep?
You can adapt to the feeling of being awake while still impaired — the subjective sleepiness fades before the performance deficit does. The evidence for genuinely reducing sleep need is very thin; the range above is what the research supports.
Do naps count toward the total?
For young children, yes, and the ranges above include them. For adults, a 20-minute early-afternoon nap adds alertness without much effect on night sleep; long or late naps usually subtract from it.
Why does the recommendation not change for athletes or pregnancy?
Because the published ranges are population guidance. Pregnancy, heavy training, illness and shift work all raise individual need, and a clinician or coach is the right source for adjusting them.