Stop waking up groggy. The problem isn't how long you sleep — it's when you wake up.
Sleep happens in 90-minute cycles. Wake up mid-cycle and you feel wrecked, no matter how many hours you logged. Wake up between cycles and you feel human. CycleWake calculates the exact times that put you between cycles — for whatever alarm you already have to set.
- Enter your wake time. Get 3 optimal bedtimes instantly.
- Enter your bedtime. Get 3 optimal wake times instantly.
- One tap sends the alarm straight to your phone's clock app.
-- No account. No subscription. No internet required.
HOW IT WORKS
1. Pick your mode.
"I need to wake up at 6:45 AM" or "I'm going to bed at 11:30 PM." Both directions. No default schedule forced on you.
2. Enter your time.
CycleWake shows your 3 best options immediately — no loading, no account creation, no permission prompts.
3. Tap a result.
Your alarm is set in your phone's built-in clock app. Samsung Clock, Google Clock, any Android clock. One tap, done.
Each result card shows the number of complete sleep cycles and total sleep time. The BEST card highlights the most practically achievable result, not just the longest one.
THE SCIENCE
Your brain cycles through light sleep, deep sleep, and REM roughly every 90 minutes. When your alarm fires mid-cycle — even after a full 8 hours — your body is dragged out of deep or REM sleep. That's the groggy, foggy, slow feeling that lasts until noon.
The fix is timing, not duration.
CycleWake adds 15 minutes to account for the average time it takes to fall asleep, so the math is accurate from when your head hits the pillow — not from when you set the alarm. This is
the detail most sleep cycle calculators skip.
WHAT'S INCLUDED
- Sleep cycle calculator — bedtime mode and wake time mode
- Instant bedtime calculator: enter wake time, get optimal sleep times
- Wake time calculator: enter bedtime, get optimal wake times
- Best time to sleep highlighted for each result
- One-tap alarm integration with your phone's clock app
- Works with Samsung Clock, Google Clock, and any default clock app
- Material You design, dark and light theme
- No account required
- No internet required
- No microphone, no sensors, no wearable needed
FREE VS. PAID
Free: calculate sleep cycles in both directions, set your first alarm.
Paid ($2.99 once): unlimited alarm scheduling, no ads. That's it.
No subscription. No annual renewal. No "premium tier." One payment, yours permanently.
Most sleep apps charge $4.99–$9.99 per month. CycleWake is $2.99 total — less than a single month of the cheapest competitor. Pay once, use every night for years.
A rewarded ad option is available inside the app if you want to extend free access without purchasing.
COMMON QUESTIONS
Does it actually set the alarm, or just tell me the time?
It sets the alarm. One tap opens your clock app with the time pre-filled. You confirm. Done. No third-party alarm engine, no battery drain, no reliability issues.
Do I need to keep the app open?
No. Once the alarm is set in your clock app, CycleWake is done. Your phone's clock handles everything from there.
Does this work with rotating schedules or irregular sleep?
Yes. There's no "your schedule" to maintain. Enter a time, get results, set an alarm. Works identically whether you use it every day or once a week with a completely different time.
Will this work on my Samsung / Xiaomi / Realme?
Yes. CycleWake uses the standard Android alarm intent, which works with every Android clock app.
Is the science real?
Yes. The 90-minute sleep cycle model is well-established in sleep research. CycleWake applies it in a straightforward calculator — no claims beyond what the math supports
Wake up at the right moment. Not just the right time. Download CycleWake and try the first calculation free.