Sleep Calculator
Sleep Cycle Calculator
Wake up feeling refreshed by sleeping in 90-minute cycles.
You should try to fall asleep at one of these times:
*We’ve factored in the average 15 minutes it takes to fall asleep.
The Science of Sleep Cycles
A good night’s sleep is more about sleep cycles than total hours. The human body sleeps in cycles that last approximately 90 minutes. Waking up in the middle of a cycle leaves you feeling groggy and tired (sleep inertia). Waking up at the end of a cycle leaves you feeling refreshed and alert.
Frequently Asked Questions
How many sleep cycles do I need?
The average adult needs about 5 to 6 sleep cycles per night, which equates to 7.5 to 9 hours of sleep.
Why do you add 15 minutes to the calculation?
Studies show that it takes the average human about 14 to 15 minutes to actually fall asleep after getting into bed. Our calculator automatically adds this buffer so your cycles align perfectly.