Free Sleep Tools to Help You Wake Up Refreshed
The free Sleep Cycle Calculator finds your perfect bedtime or wake-up time around natural 90-minute sleep cycles — because how you sleep matters more than how long you sleep.
100% free · no sign-up · works on any device
Three steps to a smarter sleep schedule
Sleep happens in repeating cycles of light sleep, deep sleep and REM. Waking at the boundary between cycles feels effortless; waking mid-cycle leaves you foggy. The calculator simply does the math for you.
Tell it your time
Enter the time you need to wake up, or the time you’re heading to bed. That’s the only input the calculator needs.
We count the cycles
It maps backward (or forward) in 90-minute sleep cycles and adds the ~15 minutes most people take to fall asleep.
Pick a cycle-friendly time
You get several ideal bedtimes or wake-up times — each one lands at the end of a full cycle so you rise feeling rested.
One full sleep cycle ≈ 90 minutes
Across a night you move through four stages of sleep, repeating roughly five to six times. The goal isn’t just more hours — it’s completing whole cycles so your body clock and your alarm finally agree.
Pick the right tool for you
Whether you’re sorting out your own bedtime or your child’s, there’s a calculator tuned for it.
Sleep timing made effortless
No fluff, no friction — just the right time to sleep and wake, worked out for you in seconds.
100% free
No paywall, no hidden upsell. Calculate as many bedtimes and wake times as you like.
No sign-up needed
Nothing to download or install. No account, no email — open it and go.
Built on sleep science
Grounded in the 90-minute cycle and the 15 minutes most people take to fall asleep.
Works on any device
Instant results in your browser on phone, tablet or desktop — anytime, anywhere.
Built for anyone chasing better mornings
If you’ve ever slept a full night and still felt wrecked, aligning your wake-up time with a complete cycle is the easiest first fix.
Students
Plan bedtimes around early classes and exam mornings without the post-alarm fog.
Busy professionals
Get the most from a short night and wake sharp for early meetings.
Shift & night workers
Rebuild a sleep schedule when your hours shift and your body clock needs a reset.
Parents & kids
Time bedtimes and naps to whole cycles for the whole family, little ones included.
Athletes
Protect the deep-sleep recovery that supports training, performance and muscle repair.
Anyone who wakes up tired
If groggy mornings are your normal, timing your wake-up to a cycle is the simplest fix to try first.
Ready for an easier morning?
Stop guessing your bedtime. Let the calculator align your sleep with your body’s natural rhythm.
Find your perfect sleep now →