What Is the Best Time to Wake Up?
Waking up groggy has nothing to do with how long you slept — it is about WHEN you wake up within your sleep cycle.
Your brain cycles through light sleep, deep sleep and REM sleep every 90 minutes. Waking in the middle of a deep sleep cycle causes grogginess that can last hours. Waking at the END of a cycle means you feel alert and refreshed immediately.
The science:
- Average time to fall asleep: 14 minutes
- One sleep cycle: 90 minutes
- Optimal cycles per night: 5–6
For a 7 AM wake-up:
- ✅ 10:46 PM (5 cycles — 7.5 hours)
- ✅ 9:16 PM (6 cycles — 9 hours)
- ⚠️ 12:16 AM (4 cycles — 6 hours)
- ❌ 1:46 AM (3 cycles — 4.5 hours)
Setting your alarm for the end of a 90-minute cycle means even 6 hours of sleep feels better than 8 hours of interrupted cycles.
Use the calculator below to find your personal best wake-up times based on when you plan to sleep.
Sleep Calculator
Find the perfect bedtime or wake-up time based on 90-minute sleep cycles. Wake up refreshed, not groggy.
What time do you want to wake up?
Why 90-minute cycles?
During sleep your brain moves through cycles of light sleep, deep sleep, and REM sleep. Each cycle takes about 90 minutes. Waking at the end of a cycle — not in the middle — is why you feel refreshed instead of groggy.
How much sleep do you need?
- Teens (14–17): 8–10 hours
- Adults (18–64): 7–9 hours
- Seniors (65+): 7–8 hours
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