Do you struggle with grogginess in the morning? Our Sleep Calculator will help you find your ideal bedtime so you wake up refreshed. Simply enter your desired wake-up time, and we’ll calculate when you should go to sleep to complete full 90-minute sleep cycles. Waking at the end of a sleep cycle helps you feel more rested, as you won’t be interrupted in deep sleep.

Sleep Calculator – Optimal Bedtime

Enter your desired wake-up time, and we’ll suggest when to go to bed for a full night’s rest:



How it works: The average adult’s sleep cycle lasts about 90 minutes. For best results, you should get 5–6 cycles per night (7.5 to 9 hours of sleep). This calculator adds about 15 minutes as an estimate for falling asleep, then counts backward from your wake-up time in 90-minute blocks. You’ll get several suggested bedtimes – for example, if you need to wake up at 6:30 AM, going to bed at 10:15 PM or 11:45 PM might be optimal. Choose the time that gives you a feasible amount of rest. Everyone is a bit different, so adjust as needed if you find you prefer slightly more or less sleep.

In addition to calculating bedtimes, we provide tips for improving sleep quality:

  • Stick to a schedule: Consistency helps your body clock. Try to go to bed and wake up at similar times each day.
  • Create a wind-down routine: dim lights, avoid screens before bed, and relax with a book or meditation.
  • Optimize your sleep environment: Keep your bedroom dark, cool, and quiet for better sleep.

Using the Sleep Calculator regularly can train you to plan bedtime better. Say goodbye to groggy mornings – with the right timing, you’ll wake up alert and energized.