There's no single magic number, but decades of research give clear ranges for each stage of life. These are the widely used general guidelines (for children, the totals include naps):
| Age group | Age | Sleep needed |
|---|---|---|
| Newborn | 0–3 months | 14–17 hours |
| Baby | 4–11 months | 12–15 hours |
| Toddler | 1–2 years | 11–14 hours |
| Preschool | 3–5 years | 10–13 hours |
| School age | 6–13 years | 9–11 hours |
| Teenager | 14–17 years | 8–10 hours |
| Young adult | 18–25 years | 7–9 hours |
| Adult | 26–64 years | 7–9 hours |
| Older adult | 65+ years | 7–8 hours |
Why sleep needs change with age
Babies and children sleep the most because sleep is when the body and brain do much of their growing and developing. Teenagers still need a lot — around 8–10 hours — but their body clock naturally shifts later, which is why early school starts leave so many of them tired. In adulthood, needs settle into the familiar 7–9 hour range. Older adults need a similar amount, but often sleep more lightly and wake more easily.
It's about quality, not just hours
Hitting the hours is only half the story. Waking in the middle of a deep-sleep stage can leave you groggy even after a full night. Sleep happens in roughly 90-minute cycles, and waking at the end of a cycle feels much better. Our sleep calculator uses this to suggest the best times to sleep or wake.
Plan the right bedtime for your age:
Open the Sleep CalculatorFor children and teens
Kids do best with a consistent bedtime routine. To work out the right bedtime from when they need to wake up, use our kids' bedtime calculator — just pick their age group. For daytime rest, our nap calculator helps keep naps short and well-timed so they don't disturb night sleep.
Signs you're not getting enough
- Needing an alarm to wake, and feeling groggy for ages after.
- Feeling sleepy during the day, especially in quiet moments.
- Relying on caffeine to get going or to push through the afternoon.
- Mood dips, poor focus, or getting sick more often.
If you consistently sleep enough hours but still feel exhausted, it's worth speaking to a doctor. This guide is general information, not medical advice.