When do you need to get up to be fit?
*Calculated with 14 min time to fall asleep + 90 min cycles.
Calculate your optimal sleep cycle. Find out when to go to bed to wake up refreshed without tiredness. Free & no app required. A useful online tool for your daily life. Calculate values quickly, for free, and without registration.
Using it is incredibly simple: Enter your values into the provided fields. The Sleep Cycle Calculator processes this data immediately and shows you the precise result. No installation or registration is required.
Save time and avoid errors with this practical calculator for daily tasks. Our tools are designed to handle complex calculations for you and provide instant answers. Optimized for desktop, tablet, and smartphone.
Yes, all our tools are 100% free.
No. All calculations happen directly in your browser. No personal data is sent to our servers.
Have you ever asked yourself: "When do I have to go to sleep to be fit in the morning?" The answer lies not in the number of hours, but in the sleep cycles.
Human sleep runs in waves. A complete cycle lasts on average 90 minutes. It consists of:
If your alarm clock rings in the middle of a deep sleep phase, you feel groggy. This is called "sleep inertia". The goal of this calculator is to wake you up at the end of a cycle when your sleep is lightest.
Our tool calculates backwards. It takes your wake-up time and calculates time windows based on the 90-minute rule plus an average of 14 minutes to fall asleep.
The average person needs about 10 to 20 minutes. Our calculator includes a flat 15-minute buffer.
No. It is based on statistical averages. Every person is individual.