Recommended hours of sleep by age
Hours per day. For the youngest groups the figure includes naps; for adults it is the night's sleep. The last column names the organisation whose recommendation the CDC cites for that row.
| Group | Age | Recommended hours | Recommended by |
|---|---|---|---|
| Newborn | 0 to 3 months | 14 to 17 | National Sleep Foundation |
| Infant | 4 to 12 months | 12 to 16 (including naps) | American Academy of Sleep Medicine |
| Toddler | 1 to 2 years | 11 to 14 (including naps) | American Academy of Sleep Medicine |
| Preschool | 3 to 5 years | 10 to 13 (including naps) | American Academy of Sleep Medicine |
| School age | 6 to 12 years | 9 to 12 | American Academy of Sleep Medicine |
| Teen | 13 to 17 years | 8 to 10 | American Academy of Sleep Medicine |
| Adult | 18 to 60 years | 7 or more | American Academy of Sleep Medicine and Sleep Research Society |
| Adult | 61 to 64 years | 7 to 9 | National Sleep Foundation |
| Adult | 65 years and older | 7 to 8 | National Sleep Foundation |
Two things stand out. The adult figure is a floor, "7 or more", not a range, and it does not drop with age as far as people assume: 7 to 8 hours at 65 and older is only an hour less at the top than for a 25-year-old. And the ranges for children are wide because children differ; a 4-year-old at 10 hours and one at 13 are both inside the recommendation.
From hours to a bedtime
The number that matters in practice is the bedtime, and it is a subtraction: alarm time minus the hours you need minus the time it takes you to fall asleep. Falling asleep is not instant, so leave a margin, say a quarter of an hour, more if you know you lie awake.
| Alarm at 6:30 am | Lights out |
|---|---|
| 7 hours (adult minimum) | 11:15 pm |
| 8 hours | 10:15 pm |
| 9 hours (teen or school age) | 9:15 pm |
| 10 hours (teen maximum) | 8:15 pm |
The sleep cycle calculator does the subtraction for any alarm time and also suggests bedtimes that end on a full sleep cycle, so the alarm is less likely to land in deep sleep. The time duration calculator is the plain version: enter when you went to bed and when you woke, and it gives the hours between.
Children and teenagers
For school-age children the recommendation of 9 to 12 hours and a school start at 7:30 means a bedtime between about 7 and 10 in the evening, including time to fall asleep. For teenagers, 8 to 10 hours against an early school start pushes lights out to before 10 pm, which is the arithmetic behind the long-running discussion about school start times. The ranges for infants and toddlers are totals over 24 hours, naps included, so a toddler who sleeps 10 hours at night and naps for two is inside the range.
What the table does not say
- It is not a maximum. The ranges describe what most people in a group need. After short nights, illness or hard training, needing more for a while is normal.
- It is not a quality measure. Eight hours interrupted five times are not the eight hours in the table. The hours are counted as sleep, not time in bed.
- It does not replace a doctor. Needing far more than the range to feel rested, loud snoring, or waking up gasping are reasons to ask one; a chart cannot tell sleep apnea from a late night.
- Weekend catch-up is not in it. The figures are per day. Five short nights and two long ones average out on paper but not in the recommendations, which are written per night.
Keeping to the hours
The simplest way to hit the number is to fix the wake time, every day including weekends, and move only the bedtime. A fixed wake time makes the evening calculation the same every day, and the countdown timer or an alarm set for the lights-out time is a better reminder than willpower. If the target feels impossible on weekdays, the table says where the problem is: for an adult with a 6:30 alarm, anything after 11:15 pm is already under the minimum.
Frequently asked questions
How much sleep does an adult need?
Seven or more hours a night for adults aged 18 to 60, according to the recommendation the CDC cites from the American Academy of Sleep Medicine and the Sleep Research Society. For 61 to 64 the National Sleep Foundation range is 7 to 9 hours, and for 65 and older 7 to 8.
How much sleep does a teenager need?
Eight to ten hours a night for 13- to 17-year-olds, per the American Academy of Sleep Medicine figures the CDC publishes. School-age children aged 6 to 12 need 9 to 12 hours.
Do naps count?
For young children the recommendations explicitly include naps: 12 to 16 hours for infants, 11 to 14 for toddlers and 10 to 13 for preschoolers are totals per 24 hours. The adult figures are for a night's sleep.
Is more than nine hours bad?
The ranges are what the expert bodies recommend for most people in each group; they are not ceilings for everyone. Someone recovering from illness or a run of short nights may need more for a while. If you regularly need far more than the range and still feel tired, that is a question for a doctor, not for a chart.
What time should I go to bed?
Count back from the alarm. For a 6:30 am alarm, seven hours of sleep plus about a quarter of an hour to fall asleep means lights out around 11:15 pm; eight hours means around 10:15 pm. The sleep cycle calculator does this and also lines the bedtime up with the end of a sleep cycle.