Sleep Cycle Calculator
Find the perfect time to fall asleep or wake up. We calculate 90-minute sleep cycles so you can wake up refreshed and energized.
You should try to fall asleep at one of these times:
Waking up between sleep cycles prevents grogginess.
The 90-Minute Sleep Cycle Wave
Your brain goes through natural waves. Waking up at the peaks prevents grogginess.
Guide & Insights
Science-Based Sleep for Peak Energy
Why feel tired after 8 hours of sleep? Our Sleep Cycle Calculator uses the 90-minute biological rhythm model to calculate the best times to wake up or fall asleep, avoiding grogginess.
Backtrack Bedtime
Set your wake-up goal, and we'll backtrack through 90-minute cycles to tell you exactly when to head to bed.
Sleep Rhythm Visualization
A unique waveform chart shows the patterns of light, deep, and REM sleep, making health advice easy to understand.
Include Sleep Latency
Accounts for the average 15-minute window it takes to fall asleep, making results more accurate for real life.
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