Sleep Calculator
Discover your optimal sleep times
Your Ideal Sleep Times
For optimal rest, try to fall asleep at one of these times:
A complete sleep cycle lasts about 90 minutes. Waking up at the end of a sleep cycle helps you feel more refreshed.
Understanding Your Sleep Needs
How Sleep Cycles Work
Sleep consists of 90-minute cycles that include both REM and non-REM stages. Completing full cycles helps you wake up feeling refreshed.
Optimal Sleep Duration
Most adults need 4-6 complete sleep cycles (6-9 hours) per night. The exact amount varies by individual and lifestyle factors.
How the Sleep Calculator Works
Our sleep calculator uses your wake-up time and estimated time to fall asleep to determine optimal bedtimes based on 90-minute sleep cycles. By waking at the end of a sleep cycle when your sleep is lightest, you’ll feel more refreshed even if you sleep fewer hours.
Why Sleep Timing Matters
Sleep quality is just as important as sleep quantity. Waking up during deep sleep can leave you feeling groggy, even after 8 hours of sleep. Our calculator helps you time your sleep to wake during lighter sleep phases.
Tips for Better Sleep
- Maintain a consistent sleep schedule, even on weekends
- Create a relaxing bedtime routine to signal your body it’s time to sleep
- Keep your bedroom cool, dark, and quiet
- Avoid screens and bright lights 1 hour before bedtime
- Limit caffeine and alcohol intake in the evening