How does the Sleep Cycle Calculator work?
The Formula
90-minute intervalsExample: Sleep at 11 PM, wake at 6:30 AM (5 cycles).
Frequently Asked Questions
How long is a cycle?
Usually 90 minutes.
Find the perfect time to wake up or go to sleep to avoid interrupting a REM sleep cycle and waking up groggy.
90-minute intervalsUsually 90 minutes.