What does this tool do?
Planning a wake time around full sleep cycles can make mornings feel easier. This calculator adds falling-asleep time and complete cycles to your bedtime and shows nearby options for four, five and six cycles.
The Formula
Wake time = Bedtime + Fall-asleep minutes + Cycles × 90 minFrequently Asked Questions
How many sleep cycles do I need?
Most adults complete four to six cycles per night. Five cycles is a common planning target, but total sleep duration and how you feel matter more.
What if I go to bed later than planned?
Shift the wake time by the same number of minutes, or accept one fewer cycle. Keeping a fixed wake time is usually better for your body clock.