Sleep Cycle Calculator

What is Sleep Cycle Calculator?

Stop waking up groggy. Sleep Cycle Calculator finds the exact time you should go to sleep or wake up — based on your body's natural 90-minute sleep cycles. Tell it when you need to wake up → get the best bedtimes Going to sleep now → get the best wake-up times Includes a nap calculator (20 / 60 / 90 min) Free, no sign-up, no ads. Built because timing your sleep cycles actually works.