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.

How to use this Sleep Calculator?

  1. Enter the time you want to wake up.
  2. Click "Calculate".
  3. Check your results!

Examples

Time you want to wake up Number of sleep cycles Suggested time of falling asleep
07:00 AM 5 11:15 PM
05:30 AM 6 08:15 PM
06:00 AM 6 8:45 PM