How Much Sleep Do You Need?
Last updated: August 2026
Most healthy adults need 7 to 9 hours of sleep a night. But the number shifts a lot across a lifetime — a newborn needs more than twice what their grandparent does — and a little between two adults of the same age.
Here's the chart by age group, the signs you're running short regardless of what the chart says, and how to find your own number from two weeks of sleep diary entries instead of guesswork.
Recommended hours of sleep by age
Consensus ranges from sleep medicine bodies and pediatric guidelines. Children's figures include naps; adults' mean one overnight block.
| Age group | Recommended sleep | Notes |
|---|---|---|
| Newborn (0–3 months) | 14–17 hours | Broken into short stretches around the clock |
| Infant (4–11 months) | 12–15 hours | Night sleep consolidates; 1–3 naps |
| Toddler (1–2 years) | 11–14 hours | Usually one afternoon nap |
| Preschool (3–5 years) | 10–13 hours | Naps often stop toward the end of this range |
| School age (6–12 years) | 9–12 hours | Early school starts are the usual squeeze |
| Teen (13–18 years) | 8–10 hours | Body clock shifts later; most teens fall short |
| Adult (18–64 years) | 7–9 hours | The standard adult range |
| Older adult (65+) | 7–8 hours | Need barely drops; sleep gets lighter and more broken |
Two misreadings to avoid. The older-adult row is not permission to sleep five hours — need barely changes after 65; getting it in one piece does. And these are hours asleep, not in bed: most people spend 20–40 minutes of a night awake, so 7.5 hours of sleep means nearly 8 between lights out and alarm.
Signs you're not getting enough
The chart is a starting point; your body is the evidence. Chronic short sleep is easy to miss because the tiredness stops feeling like tiredness and starts feeling like your personality:
- You need an alarm every day and snooze it more than once.
- You sleep dramatically longer on days off — a two-hour lie-in is debt being repaid.
- You fall asleep within five minutes. Normal is 10–20; instant is deprivation, not talent.
- Afternoon crashes pushed through with caffeine after 3pm.
- Micro-sleeps — a lost second in a meeting, a mile of road you don't remember. Act on this one immediately.
- Irritability and low mood out of proportion to events.
- Foggy recall — re-reading the same paragraph, losing words mid-sentence.
- More colds, stronger cravings for fast carbohydrates.
People reliably underestimate their own impairment — performance keeps declining while the felt sleepiness plateaus. If several of these are familiar, trust the list over your sense of coping.
Why your number might not be 8
"Eight hours" is an average, not a rule. Where you sit in the 7–9 range is largely genetic and stable through adulthood. Genuine short sleepers who thrive on about 6 hours exist, as do long sleepers who need 9 or more — both far rarer than the people who claim to be short sleepers.
Some things legitimately push you to the top of the range for a while: hard physical training, illness and recovery, pregnancy (especially the first trimester), adolescence — 8–10 hours needed and a late-running body clock — and any debt from previous short nights.
To find your figure, record two weeks of sleep on a stretch with no alarm — a holiday works. The first nights run long while you pay off debt; the number your body settles on is your baseline. Our sleep calculator then works backwards from your wake time to a bedtime that fits.
Sleep debt: can you catch up?
Partly. Six hours a night Monday to Friday leaves you roughly ten hours short by Saturday, and a long lie-in genuinely recovers some of it — the body prioritizes the deepest stages first, which is why recovery sleep feels disproportionately good (see sleep cycles and stages). But the debt isn't free: attention and metabolic markers don't fully recover over a weekend, and short weekdays plus long weekends swing your body clock like jetlag — Sunday night gets harder, Monday worse.
Better to shrink the debt at the source: bedtime earlier 15–20 minutes at a time, wake time steady all seven days, and the lie-in shrinks on its own. In bed on time but still can't drop off? Different problem — see how to fall asleep faster.
Notebook vs app: an honest comparison
Finding your number takes two weeks of honest records, and a notebook by the bed does that fine — if you'll write in it. Its failure mode: you skip the night you got in late, exactly the night that mattered, then face arithmetic on scribbled times.
An app handles the boring parts: sleep and wake times with time slept computed, charts that make the weekday–weekend gap visible, a quality rating plus dream and note fields so you can see whether more hours buy better nights, bedtime reminders for those 15-minute shifts, Apple Health sync, and export to PDF, XLSX, CSV or JSON for a doctor — with iCloud sync and no account or email. Feeltracker Sleep & CPAP is a manual sleep diary, not an automatic stage tracker: you tell it when you slept, and it records what actually happened rather than an accelerometer's guess — then does the averaging for you.
Frequently asked questions
Is 6 hours of sleep enough?
For almost everyone, no. True short sleepers are rare, and people restricted to 6 hours keep declining on attention tests while *feeling* like they've adapted. If you rely on an alarm, crash in the afternoon, or sleep much longer on days off, 6 hours isn't enough for you.
Do older adults need less sleep?
Barely — the recommendation drops from 7–9 hours to about 7–8 hours after 65. What changes is sleep *architecture*: nights get lighter and more fragmented, and the body clock shifts earlier. Persistent daytime sleepiness is worth raising with a doctor, not accepting as aging.
How much sleep do teenagers need?
8–10 hours, and most don't get it. Adolescence shifts the body clock later — a teenager genuinely can't fall asleep at 9pm — and early school starts cut the other end. Protecting the weekend wake-up time and keeping screens out of the last hour help more than lecturing about bedtime — see sleep hygiene.
Can I train myself to need less sleep?
No. You can train yourself to *tolerate* less — the subjective sleepiness fades — but the measurable impairment doesn't. Sleep need is largely genetic and stable through adulthood.
How do I know if I'm sleeping enough?
The cleanest test: on a stretch with no alarm, how long do you sleep once the first few catch-up nights are behind you? That's your number. Log two weeks in a sleep diary and compare it to a work night — the gap is your weekday debt.
