Sleep calculator
Enter your wake-up time and get optimal bedtimes calculated in 90-minute sleep cycles, adjusted for how long you take to fall asleep.
Go to bed at:
- 21:156 cycles · 9 h
- 22:455 cycles · 7.5 h
- 00:154 cycles · 6 h
A sleep cycle averages 90 min, but ranges 70–120 min. Treat the result as a starting point, not gospel.