Sleep Calculator

Calculate the time you should fall asleep to reach the certain number of sleep cycles.

Enter the time you want to wake up:
Result:
Waiting for Input...

Sleep Calculator calculates what time to fall asleep to reach a certain number of 90-minute sleep cycles.

A good night's sleep should consist of 5-6 cycles.

Examples

Time you want to wake up Number of sleep cycles Suggested time of falling asleep
07:00 5 23:15
05:30 6 20:15