Sleep needs change significantly across your lifetime, starting at 14 to 17 hours a day for newborns and gradually declining to 7 or 8 hours for older adults. The CDC breaks these recommendations into nine age groups, each reflecting shifts in brain development, hormonal changes, and physical growth that make sleep more or less demanding at different stages of life.
Recommended Sleep by Age Group
- Newborns (0 to 3 months): 14 to 17 hours
- Infants (4 to 12 months): 12 to 16 hours, including naps
- Toddlers (1 to 2 years): 11 to 14 hours, including naps
- Preschoolers (3 to 5 years): 10 to 13 hours, including naps
- School-age children (6 to 12 years): 9 to 12 hours
- Teenagers (13 to 17 years): 8 to 10 hours
- Adults (18 to 60 years): 7 or more hours
- Adults (61 to 64 years): 7 to 9 hours
- Older adults (65 and up): 7 to 8 hours
These ranges represent total sleep in a 24-hour period, not just nighttime. For children under 5, naps count toward the daily total. The ranges exist because individual needs vary. Some toddlers thrive at 11 hours while others need closer to 14. What matters is landing consistently within your age group’s range.
Why Babies and Toddlers Need So Much Sleep
Newborns spend roughly half their sleep time in REM, the lighter stage associated with dreaming and rapid eye movement. That’s a much larger proportion than older children or adults get. This heavy REM load supports the enormous amount of brain wiring happening in the first months of life.
For infants and toddlers, the recommended hours include both overnight sleep and daytime naps. Young toddlers often still take two naps a day, but most drop to one nap by around 18 months. By preschool age, many children get all their sleep at night and stop napping altogether. If your preschooler resists naps but sleeps 10 to 13 hours at night and seems well-rested during the day, that’s perfectly fine.
The Teenage Sleep Shift
Teenagers need 8 to 10 hours, but biology works against them. During puberty, the body’s internal clock shifts later. The natural sleep cycle of a healthy adolescent runs about 24.27 hours, slightly longer than a full day, which means their preferred bedtime drifts progressively later. On top of that, teens build up the urge to sleep more slowly than younger children do, making it easier for them to stay awake late into the evening.
The result is a mismatch between biology and school schedules. Surveys consistently show that about 70% of middle and high school students need a parent to wake them on school mornings. In one study, 61% of high schoolers reported being too sleepy to get out of bed, and a Swiss study found roughly 63% of 15- to 17-year-olds felt tired upon waking. This isn’t laziness. It’s a measurable delay in the circadian system that makes early wake times genuinely difficult during adolescence. When school start times force teens to rise before their body is ready, the lost sleep accumulates into chronic deprivation that affects mood, focus, and academic performance.
Adult Sleep: The 7-Hour Floor
For adults between 18 and 60, the CDC recommends 7 or more hours per night. That “or more” is intentional. Seven hours is the minimum, not a target. Some adults function best at 8 or even 9 hours. The key marker is how you feel during the day: if you’re relying on caffeine to stay alert, struggling with concentration in the afternoon, or falling asleep within minutes of lying down, you’re likely not getting enough.
Consistently sleeping fewer than 7 hours raises the risk of obesity, type 2 diabetes, high blood pressure, heart disease, stroke, anxiety, and depression. Short sleep also increases the likelihood of motor vehicle crashes and workplace errors. These aren’t risks that kick in only after years of deprivation. Even a week or two of restricted sleep can impair decision-making and reaction time in measurable ways.
Pregnancy adds another layer. Women who sleep fewer than 6 hours in a 24-hour period during pregnancy face higher rates of preeclampsia, gestational diabetes, longer labors, and cesarean delivery. If you’re pregnant and struggling with sleep, prioritizing rest is worth the effort even when discomfort makes it harder.
How Sleep Changes After 65
The recommended range narrows slightly for older adults, to 7 to 8 hours, but the bigger change is in sleep quality. Older adults tend to spend less time in deep sleep, the restorative stage that helps with tissue repair and immune function. Periods of deep sleep become shorter and less frequent. Sleep also becomes more fragmented, with brief awakenings throughout the night that may or may not be noticeable.
These changes are a normal part of aging, not a sign of a sleep disorder. But they do mean that an older adult might spend 8 hours in bed yet only sleep for 6.5 of them. Sleep efficiency, the percentage of time in bed actually spent asleep, is considered healthy at 85% or above. If you’re lying awake for long stretches in the middle of the night, the issue may not be how many hours you’re aiming for but how much of your time in bed is productive sleep.
Quality Matters as Much as Hours
Hitting the right number of hours doesn’t guarantee restful sleep. Sleep quality depends on cycling through all the sleep stages multiple times per night, including the deep sleep stages that leave you feeling refreshed. Frequent awakenings, long stretches of light sleep, or spending excessive time in bed trying to fall asleep all erode the benefit of a technically adequate number of hours.
A few signs that your sleep quality needs attention, even if you’re logging enough hours: waking up feeling unrefreshed, needing more than 30 minutes to fall asleep most nights, or waking up multiple times and struggling to get back to sleep. These patterns are worth addressing at any age, because 7 hours of fragmented, light sleep doesn’t deliver the same benefit as 7 hours of consolidated, efficient sleep.