Sleep Calculator

Sleep Calculator suggests natural wake-up times for your body that match how sleep cycles works. Most people sleep in repeating cycles of about 90 minutes (light sleep → deep sleep → REM). If you wake up in the middle of a cycle, you’re more likely to feel groggy. If you wake up at the end of a cycle, you usually feel better. Sleeping 5-6 cycles is ideal for most people.

✅ Why this helps

Waking up between cycles will help you feel lighter, clearer, and more refreshed. Instead of waking up groggy and sluggish, you’ll have more energy to start your day.

Sleep Calculator uses the current time, the amount of time you usually take to fall asleep (you can change this in Advanced Settings), and these 90-minute cycles to recommend the best wake-up times.

Sleep cycles guide

• 🟢 5–6 cycles: ideal for most people. You'll wake up feeling best.

• 🟡 4 or 7 cycles: acceptable when needed, but not optimal.

• 🔴 Fewer than 4 or more than 7 cycles: not recommended for overall health and energy.