Newborns (0-3 months)
14 to 17 hours per day, though this is typically spread across multiple shorter sleep periods rather than one continuous stretch, since newborns don't yet have a settled day-night sleep cycle.
Infants and toddlers (4 months-2 years)
Infants generally need 12-16 hours including naps, while toddlers (1-2 years) need around 11-14 hours as naps gradually become less frequent.
Children (3-13 years)
Preschoolers typically need 10-13 hours, while school-age children (6-13) generally need 9-11 hours. Consistent sleep during these years is strongly linked to attention, behavior, and learning outcomes.
Teenagers (14-17 years)
8-10 hours is the generally recommended range, though most teenagers get meaningfully less than this due to early school start times combined with a natural biological shift toward staying up later during adolescence.
Adults (18-64 years)
7-9 hours is the standard recommendation for most adults. Consistently sleeping less than 7 hours is associated with a range of negative health outcomes over time, even if it doesn't feel noticeably harmful day to day.
Older adults (65+)
7-8 hours is still generally recommended, though sleep often becomes lighter and more fragmented with age, and many older adults naturally wake earlier than they did when younger.
Why sleep cycles matter, not just total hours
Sleep happens in roughly 90-minute cycles, and waking up in the middle of a cycle — rather than between cycles — is a major reason people feel groggy even after what should be enough total sleep. Timing your wake-up to align with the end of a cycle can make a real difference to how rested you feel.