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:
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!

For example:

Sleep Calculator Example


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