Sleep Calculator

Calculate the best times to fall asleep or wake up based on 90-minute sleep cycles. Waking up between cycles helps you feel more refreshed and alert.

☀️I need to wake up at...
🌙I want to go to bed at...
💤I want to sleep now

What time do you need to wake up?

:

You should go to sleep at:

It takes the average person 14 minutes to fall asleep. These times account for that.

😴 What is a Sleep Cycle?

A sleep cycle lasts about 90 minutes and includes light sleep, deep sleep, and REM sleep. Completing full cycles (rather than waking mid-cycle) is key to feeling rested.

💡 Why 90 Minutes?

Research shows that each sleep cycle takes approximately 90 minutes. Waking at the end of a cycle (during light sleep) makes you feel more alert than waking during deep sleep.

🌟 Tips for Better Sleep

Keep a consistent schedule, avoid screens 1 hour before bed, keep your room cool (65-68°F), limit caffeine after 2 PM, and exercise regularly but not too close to bedtime.

Recommended Sleep by Age

Age GroupRecommended HoursSleep Cycles
Newborn (0-3 mo)14-17 hours9-11 cycles
Infant (4-11 mo)12-15 hours8-10 cycles
Toddler (1-2 yr)11-14 hours7-9 cycles
Preschool (3-5 yr)10-13 hours7-9 cycles
School Age (6-13 yr)9-11 hours6-7 cycles
Teen (14-17 yr)8-10 hours5-7 cycles
Adult (18-64 yr)7-9 hours5-6 cycles
Senior (65+ yr)7-8 hours5 cycles