Free bedtime calculator

What time should I go to bed?

Choose the time you must wake up and our calculator will show several suggested bedtimes. The estimates use 90-minute planning intervals and allow about 15 minutes to fall asleep.

Calculate your bedtime now

Open the calculator, select your wake-up time and choose the option that gives you enough total sleep.

Use the sleep calculator

How the bedtime calculator works

The tool counts backwards from your alarm time in estimated sleep-cycle blocks. Earlier results provide more total sleep; later results are shorter options for nights when your schedule is limited.

  1. Select the hour and minute you need to wake up.
  2. Choose AM or PM and calculate your bedtimes.
  3. Prefer an option that provides at least the recommended amount of sleep for your age.

Sleep cycles vary between people and throughout the night. These times are estimates, not a way to detect your actual sleep stage.

Example: waking at 7:00 AM

With a 15-minute settling-in allowance, common cycle-based suggestions include approximately 9:45 PM for six cycles or 11:15 PM for five cycles. Your ideal time may differ depending on sleep needs and how quickly you fall asleep.

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