Kids’ sleep needs change fast as they grow, and the “right” bedtime for a toddler is very different from what works for a ten-year-old. This calculator uses your child’s age and either their wake-up time or bedtime to work out a target that actually matches how much sleep kids their age need.
Quick answer: Recommended nightly sleep ranges from about 12–16 hours a day for infants down to 8–10 hours a night for teenagers, per the American Academy of Sleep Medicine. Pick your child’s age below, tell the calculator either their wake-up time or bedtime, and it works out the other one for you.
Who This Is For
This is for parents trying to set (or fix) a bedtime routine and wanting a number grounded in actual pediatric sleep guidelines rather than a guess. It works whether you’re starting from a school wake-up time you can’t change, or trying to figure out what time your child should be waking up given the bedtime you’ve already settled on.
Calculate Your Child’s Bedtime
How This Calculator Works
The American Academy of Sleep Medicine (AASM) publishes consensus recommendations for how much sleep children need across a 24-hour period, by age:
- 4–12 months: 12–16 hours (including naps)
- 1–2 years: 11–14 hours (including naps)
- 3–5 years: 10–13 hours (including naps)
- 6–12 years: 9–12 hours
- 13–18 years: 8–10 hours
The calculator takes the midpoint of the recommended range for your child’s age, subtracts any daytime nap time you enter (for ages where napping is typical), and adds a 15-minute buffer for the time it usually takes to actually fall asleep once in bed. That gives a nighttime sleep target, which is then used to calculate bedtime from a wake-up time, or wake-up time from a bedtime.
This is a starting point based on population averages, not an exact number for your specific child — some kids consistently need more or less sleep than the average for their age, and that’s normal as long as they’re waking up rested and functioning well during the day.
Common Mistakes
- Changing bedtime by a lot all at once. If your child’s current bedtime is far from the calculated one, shift it gradually — 15 minutes every few days — rather than all at once, which usually backfires with bedtime resistance.
- Ignoring nap time for younger kids. A toddler who naps 2 hours during the day needs meaningfully less sleep at night than one who doesn’t nap at all — skipping the nap adjustment will push bedtime too early.
- Not accounting for wake windows in infants under 4 months. This calculator starts at 4 months because sleep patterns before that are highly irregular and don’t follow the same consolidated-nighttime-sleep model — talk to your pediatrician for guidance on newborn sleep specifically.
Key Takeaways
- Recommended sleep drops steadily with age, from 12–16 hours for infants to 8–10 hours for teenagers.
- Nap time counts toward the daily total for younger kids — more napping generally means a later, not earlier, bedtime works fine.
- A consistent bedtime and wake time matter as much as hitting the exact recommended number.
- Treat any calculated time as a starting point, not a strict rule — adjust based on how your child actually seems during the day.
Frequently Asked Questions
What if my child doesn’t nap anymore but is still under 5?
Just leave the nap field at 0. Many kids drop naps earlier than the “typical” age for their group, and once that happens, all of their recommended sleep needs to happen at night — which usually means an earlier bedtime than nap-still-happening peers.
My child wakes up earlier than the calculated wake-up time. Is that a problem?
Not necessarily — some early waking is normal, especially in younger kids. If it happens consistently and your child seems tired during the day, it may be worth trying an earlier bedtime rather than trying to make them sleep later, since overtired kids often wake up earlier, not later.
How accurate is the 15-minute fall-asleep buffer?
It’s a reasonable average, but some kids fall asleep faster and some take longer, especially during a bedtime routine transition. If you know your child reliably takes longer to fall asleep, start the bedtime routine that much earlier.
Does screen time before bed affect these numbers?
This calculator doesn’t adjust for it directly, but screen exposure close to bedtime is well-documented to delay sleep onset, which effectively extends that 15-minute buffer. Cutting screens out in the hour before the calculated bedtime generally makes the calculated time more accurate.
About this article: This calculator applies general pediatric sleep-duration guidelines from the American Academy of Sleep Medicine. It’s a starting point for building a bedtime routine, not a personalized medical assessment — persistent sleep problems in children are worth discussing with a pediatrician.