Sleep cycle calculator

Sleep Calculator

Find a better bedtime or wake-up time using 90-minute sleep cycles.

--:-- Your current time

Recommended bedtimes

Choose a time that lets you wake up between sleep cycles.

How the sleep calculator works

A full sleep cycle is commonly estimated at about 90 minutes. This calculator adds your selected fall-asleep time, then suggests sleep or wake times around complete cycles.

For many adults, 5 to 6 complete cycles is a useful target. Your personal schedule, health, age, and sleep quality can change what feels best.