Find Your Perfect Sleep Schedule
Calculate the best times to fall asleep or wake up based on 90-minute sleep cycles
How the Sleep Calculator Works
Humans sleep in 90-minute cycles. Waking up in the middle of a cycle makes you feel groggy — waking up at the end of a cycle leaves you refreshed!
- We assume it takes ~15 minutes to fall asleep
- Adults need 3 to 6 full cycles per night (4.5–9 hours)
- Best results: 6 cycles (9 hours), 5 cycles (7.5 hours), or 4 cycles (6 hours)
Pro tip: Aim for wake-up times that align with the end of a sleep cycle — you’ll feel energized and alert!