Sleep – Sleep Cycle Calculator
Improve your sleep with sleep cycles
Our sleep calculator helps you find the best time to go to bed or wake up based on your sleep cycles. Simply enter the time you want to wake up, and the tool will suggest several ideal bedtimes. You can also do the reverse by entering the time you plan to go to bed to find out the best time to set your alarm.
This tool uses the average duration of a sleep cycle, which is approximately 90 minutes, to suggest time slots that correspond to the end of a complete cycle. Waking up in the middle of a sleep cycle often explains that feeling of tiredness in the morning, even after a long night's sleep.
What is a sleep cycle?
A sleep cycle lasts approximately 90 minutes, during which the body goes through different phases: light sleep, deep sleep, and REM sleep. In a single night, we typically go through 4 to 6 cycles depending on the individual. It's at the end of each cycle that waking up feels the most natural and least jarring for the body.
The online sleep calculator uses these cycles to suggest bedtimes and wake-up times tailored to your rhythm. It also accounts for the average time it takes to fall asleep, which is about 15 minutes.
Why calculate your sleep cycles?
An online sleep calculator can be very useful for understanding your rhythm and improving your nights. It can help you figure out what time to go to bed when you need to wake up early the next day, or determine the ideal wake-up time when you're going to bed late. It also helps you better organize your sleep if you work shifts, understand why you wake up tired despite getting enough hours, or adjust your alarm to the most favorable moment.
Athletes also use it to optimize their recovery, and students use it to better organize their study sessions.
Sleep better by following your cycles
The main benefit of our sleep calculator is that it helps you sleep better without necessarily sleeping longer. By waking up at the right point in your cycle, you often feel more rested than after a longer night that was interrupted at the wrong time.
Our tool runs directly in your browser and works on all platforms: mobile, tablet, or desktop. Our calculator gives you a reliable estimate in just a few seconds, without having to wear a device at night and without any installation or sign-up required, unlike traditional sleep tracking apps.
It's much easier to adjust your sleep schedule and feel energized every day, whether it's for work, studying, or simply enjoying your days. Keep in mind that everyone is different and that the ideal amount of sleep depends on age and lifestyle. It's perfect for finding out what time to go to bed or setting your alarm at the best point in your sleep cycle.