Sleep Calculator
Find the best bedtime using sleep cycles.
Go to bed at one of these times:
Based on 90-minute sleep cycles plus ~15 minutes to fall asleep. A general guide, not medical advice.
About Sleep Calculator
Wake up between sleep cycles to feel more refreshed. Tell the calculator when you want to wake up (or that you're going to sleep now) and it suggests times based on 90-minute cycles.
- 1Choose wake-up time or 'sleep now'.
- 2Read the suggested times.
- 3Pick the option with enough full cycles.
FAQ
Why 90 minutes?
A full sleep cycle is roughly 90 minutes; waking at the end of one tends to feel easier than mid-cycle.