How Much Sleep Do You Need by Age?
Drag the slider to your age — see your recommended sleep hours and how many 90-minute sleep cycles that translates to each night.
| Age Group | Recommended Sleep | Sleep Cycles | Key Notes |
|---|---|---|---|
| Newborns (0–3 mo) | 14–17 hours | Polyphasic | No structured cycles yet |
| Infants (4–11 mo) | 12–16 hours | Polyphasic | Includes daytime naps |
| Toddlers (1–2 yrs) | 11–14 hours | ~7–9 cycles | Shorter ~60-min cycles |
| Preschool (3–5 yrs) | 10–13 hours | ~7–9 cycles | Napping normal & beneficial |
| School Age (6–12 yrs) | 9–12 hours | ~6–8 cycles | Deep sleep peaks; critical for learning |
| Teenagers (13–17 yrs) | 8–10 hours | ~5–7 cycles | Circadian phase delay is normal |
| Young Adults (18–25) | 7–9 hours | ~5–6 cycles | Adult 90-min cycles established |
| Adults (26–64 yrs) | 7–9 hours | ~5–6 cycles | Consistent needs throughout |
| Older Adults (65+) | 7–8 hours | ~5–6 cycles | Quality becomes increasingly key |
Source: AASM Consensus Statement on Recommended Sleep Duration
Why sleep needs change with age
Sleep architecture changes profoundly over a lifetime. Newborns spend up to 50% of their sleep in REM — a proportion that drops to around 20–25% by adulthood. This is because REM sleep is critical for brain development in infancy.
Teenagers experience a well-documented circadian phase delay: their internal clock genuinely shifts later, making early morning wake times biologically difficult. This isn't laziness — it's physiology.
In older adults, slow-wave (deep) sleep decreases by roughly 2% per decade after age 30. The need for sleep doesn't diminish — what changes is the ability to achieve deep sleep efficiently, making sleep quality increasingly important.
Find your perfect bedtime
Now that you know how many hours you need, use SnoozeCalc to find the exact times based on 90-minute sleep cycles.
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