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Sleep Time Calculator

Calculate the best bedtime or wake-up time based on 90-minute sleep cycles.

Includes 15 minutes to fall asleep. Each sleep cycle = 90 minutes.

Recommended Sleep by Age

Newborn (0–3 months)14–17 hours
Infant (4–11 months)12–15 hours
Toddler (1–2 years)11–14 hours
Preschool (3–5 years)10–13 hours
School-age (6–13 years)9–11 hours
Teen (14–17 years)8–10 hours
Adult (18–64 years)7–9 hours
Older adult (65+)7–8 hours

About Sleep Calculator

Sleep Calculator suggests optimal bedtimes or wake times based on 90-minute sleep cycle intervals. Enter when you need to wake up and see the best times to fall asleep, or enter your bedtime to see ideal wake-up times. Waking at the end of a cycle leaves you feeling more refreshed.

  • 90-minute sleep cycle timing
  • Best bedtimes for target wake time
  • Best wake times for target bedtime
  • Sleep cycle count display