Enter your desired wake-up time to calculate the best times to go to sleep. Sleep does not occur in one continuous block, but instead happens in cycles that last around 90 minutes.
It is easier for the body to wake up at the end of a sleep cycle rather than in the middle of deep sleep. Waking up during a cycle can make you feel tired and groggy, even if you have slept for many hours.
This calculator works by counting backwards in 90-minute intervals from your wake-up time. It then suggests bedtimes that allow you to complete full sleep cycles, helping you wake up feeling more refreshed.