Sleep Calculator

Sleep Cycles & Wake Times

Waking up groggy often happens because your alarm goes off in the middle of a deep sleep cycle. A typical sleep cycle lasts about 90 minutes.

This calculator works backwards from your desired wake-up time to find the optimal times to fall asleep, allowing you to wake up at the end of a cycle when you are in a lighter sleep stage.

• 6 Cycles (9 hours): Recommended for athletes or those needing recovery.
• 5 Cycles (7.5 hours): The average recommended sleep duration for most adults.
• 4 Cycles (6 hours): A shorter night, but still timed to avoid grogginess.

*The calculator adds an average of 15 minutes to allow for falling asleep.