Sleep Calculator for Kids: Bedtimes and Sleep Routines by Child Age
Children require substantially more sleep than adults because Human Growth Hormone (HGH) is released almost exclusively during Stage N3 slow-wave deep sleep. School-age children (ages 6–12) require 9 to 12 hours of sleep per night. To set a consistent bedtime, work backwards from school wake-up times and add a 30-minute wind-down routine without screens.
The Biology of Child Sleep and Growth Hormone
During deep Stage N3 sleep, the pituitary gland releases pulses of Human Growth Hormone that fuel bone growth, muscle repair, and immune maturation. For deeper context, see our related guides on pediatric sleep by age guide and infant nap transitions.
Children also spend more time in slow-wave sleep than adults, which explains why waking a sleeping child mid-cycle is notoriously difficult.
Kids Bedtime Chart by Wake-Up Alarm
Use this lookup table to determine bedtime based on school start alarms:
| Wake-Up Time | Preschool (3–5 yrs, 11 hrs) | School-Age (6–9 yrs, 10 hrs) | Pre-Teen (10–12 yrs, 9.5 hrs) |
|---|---|---|---|
| 6:30 AM | 7:30 PM | 8:30 PM | 9:00 PM |
| 7:00 AM | 8:00 PM | 9:00 PM | 9:30 PM |
| 7:30 AM | 8:30 PM | 9:30 PM | 10:00 PM |
Managing Screens and Blue Light in Children
Children’s eyes have larger pupils and clearer lenses than adults, making them twice as sensitive to blue light from tablets and televisions. Shut off screens 60 minutes before bed.
Calculate Your Personalized Sleep Schedule
Eliminate guesswork. Use our free, evidence-based sleep calculators to synchronize your alarms with your biology.
Related Pediatric Sleep Guides
Deepen your circadian science and sleep scheduling knowledge with these companion guides:
Frequently Asked Questions
What time should a 7-year-old go to bed?
A 7-year-old needs 10 to 11 hours of sleep. If waking up at 7:00 AM, lights-out should be between 8:00 PM and 8:30 PM.
How does lack of sleep affect children?
Sleep deprivation in children mimics symptoms of ADHD, including hyperactivity, emotional volatility, impulsivity, and impaired school concentration.
Our editorial research team specializes in sleep chronobiology and circadian rhythm science, translating peer-reviewed polysomnography protocols into accessible digital tools. All sleep models are verified against American Academy of Sleep Medicine (AASM) standards.