Sleep Calculator

Find the best bedtimes or wake-up times based on 90-minute sleep cycles — pick a wake-up time to see when to fall asleep, or a bedtime to see when to wake.

To wake up refreshed, try falling asleep at one of these times:

  • 21:45 6 cycles · 9 h
  • 23:15 5 cycles · 7.5 h
  • 0:45 4 cycles · 6 h
  • 2:15 3 cycles · 4.5 h