Calculate your ideal sleep and wake-up times based on natural sleep cycles.
A sleep cycle is a repeating pattern of sleep stages that includes light sleep, deep sleep, and REM sleep.
A complete sleep cycle usually lasts around 90 minutes. Planning sleep around these cycles may help you wake up feeling more refreshed.
A typical sleep cycle lasts around 90 minutes, although it can vary between people.
Many adults feel rested after around 4–6 complete sleep cycles.
Waking between cycles may help some people feel less groggy.
It helps plan sleep timing but does not replace healthy sleep habits.