Sleep Calculator
Add time to fall asleep and the chosen number of 90-minute cycles to bedtime.
This calculator is free to use. Enable JavaScript to enter your values and see a result instantly.
How it works
Add time to fall asleep and the chosen number of 90-minute cycles to bedtime.
Worked example
Five cycles correspond to about 7.5 hours of sleep.
Keep in mind
Real sleep cycles vary; prioritize adequate sleep over exact cycle timing.