Sleep Calculator — Find the Best Time to Sleep or Wake Up

Free sleep calculator based on 90-minute sleep cycles. Find the best time to wake up or go to bed and wake up refreshed every time.

Sleep Now — Calculate Your Wake-Up Time

Enter your current bedtime and instantly get the optimal wake-up times based on natural 90-minute sleep cycles, including 14 minutes to fall asleep.

Calculate wake-up time

Wake Up At — Calculate Your Bedtime

Set your desired wake-up time and find out the best time to go to bed so you complete full sleep cycles and wake up feeling rested.

Calculate bedtime

About Sleep Cycles

Each sleep cycle lasts roughly 90 minutes and includes light sleep, deep sleep, and REM stages. Waking between cycles — rather than in the middle of one — helps you feel alert instead of groggy. Most adults need 4 to 6 complete cycles per night (6 to 9 hours).

Why 14 Minutes?

The average healthy adult takes about 14 minutes to fall asleep. This sleep calculator factors in that sleep onset latency so your cycle timing stays accurate.

REM Sleep

REM (Rapid Eye Movement) sleep is when most dreaming occurs and plays a key role in memory consolidation and emotional processing. Later sleep cycles contain more REM sleep.