Myth: everyone needs exactly eight hours of sleep
Why sleep needs are a range, and how to find yours.
By Best Sleep Trackers · Updated October 18, 2026
The myth
“Everybody needs eight hours. If you get less, something is wrong.”
What the guidelines say
- The American Academy of Sleep Medicine and Sleep Research Society recommend that adults sleep 7 or more hours a night on a regular basis (consensus statement).
- The National Sleep Foundation suggests 7–9 hours for adults and 7–8 hours for older adults (NSF, 2015).
- Children and teens need more: 8–10 hours for teens and up to 13 hours for preschoolers (AASM, 2016).
So eight hours is simply in the middle of the adult range.
How to find your number
Two simple clues: how you feel in the morning, and how you feel mid-afternoon. If you wake easily and stay alert without lots of caffeine, your current sleep is probably about right. If you’re sleepy most days, try adding 15 minutes to your sleep for a week.
See where your age falls on our sleep needs chart, and use the bedtime calculator to build a bedtime around your number.
Sleeping much more or less than the usual range, or feeling unrested regardless, is worth mentioning to a doctor.
Sources
Related articles
- Adult sleep Sleep cycles explained (and how accurate the 90-minute rule is) What happens during a night of sleep, what a cycle is, and why 90 minutes is an average rather than a rule.
- Baby and toddler sleep Baby wake windows by age: what the ranges really mean How long babies are usually comfortable awake between sleeps, why the numbers vary so much, and how to use them gently.
- Kids’ sleep How much sleep does my child need? Recommended hours of sleep for babies, toddlers, school-age children and teens, and how to turn them into a bedtime.
General information only. This tool gives general sleep information and is not a substitute for medical advice. If you're worried about your sleep or your child's, talk to a doctor or pediatrician.