📖 About

Our advanced sleep calculator learns from your sleeping habits and estimates accordingly the best times to wake up or fall asleep. Depending on your age and specific sleep cycle, several different times will be given. To tailor our calculator to your unique needs, you will be asked how you feel after waking up. As you continue to use the calculator over time, the algorithm will be able to provide more accurate suggestions.

♻️ Sleep Cycles

Have you ever noticed how sometimes you wake up feeling refreshed even when you sleep much less than usual? Or sometimes you feel tired even after sleeping more than usual? This is because of sleep cycles.

In short, while you sleep, your brain goes through 4 stages of sleep which last a total of around 90 to 120 minutes. Your level of fatigue depends on when you wake up within this cycle. The best time to feel energetic is to wake up at the end of each cycle.

(Your sleep cycle length is defaulted to 90 minutes because you do not have enough sleep data. Get 3 more samples to get a more accurate result.)

😴 Stages of Sleep Cycle

Typically within one night you will repeat this cycle of four stages 4 to 6 times.

• Stage 1 (5%): Your brain begins to slow down and you enter light sleep.
• Stage 2 (45%): Deeper sleep begins. You are less likely to be awakened as your heart rate and temperature drop.
• Stage 3 (25%): This is the deepest stage of sleep and the most difficult to wake from. At this point your body begins to repair. This stage is needed for a good night's sleep and being awoken during this time leads to mental fogginess.
• Stage 4 (25%): Dreaming starts at this stage. It is generally not considered a restful sleep stage. If you are awakened at this point you will also feel severely tired.

🔒 Privacy

We respect your privacy, and acknoledge that not everyone wants the internet to know about their sleep habits. Therefore, all data collected is stored on your browser, and never sent to a server.