Go to bed at one of these times (each is a full set of 90-minute sleep cycles):
Set your alarm for one of these times to wake between sleep cycles:
Frequently Asked Questions
How does the sleep calculator work?
Sleep happens in roughly 90-minute cycles. Waking at the end of a cycle (rather than the middle) helps you feel more refreshed. The calculator counts back or forward in 90-minute cycles, allowing about 15 minutes to fall asleep.
Find the best times to go to sleep or wake up based on 90-minute sleep cycles.