Sleep Calculator
Wake up refreshed every morning. Built on 90-minute sleep cycle science to find your optimal bedtime, wake time, or nap schedule.
What time do you want to wake up?
Includes 14 minutes average sleep onset time
Why Complete Cycles Matter
Each 90-minute sleep cycle includes light sleep, deep sleep, and REM. Waking mid-cycle triggers sleep inertia β that groggy, heavy feeling. Timing your alarm to the end of a cycle means you wake during light sleep, feeling alert and refreshed naturally.
Choose your nap type
When are you starting your nap?
β‘ Pro Napping Tips
Nap between 1β3 PM when your body naturally dips in alertness β aligns with your circadian rhythm.
Try a 'coffee nap': drink coffee right before your 20-min nap. Caffeine kicks in just as you wake!
Keep naps under 30 min unless you have 90 min. The 30β60 min zone causes the most grogginess.
Use an eye mask and earplugs. Even 10 minutes of quality dark quiet sleep is restorative.