Advanced Sleep Calculator
Optimize your wake-up times based on 90-minute REM cycles to wake up feeling energized, not groggy.
Suggested Bedtimes
hotel
10:30 PM
9 Hours • 6 Cycles
hotel
12:00 AM
7.5 Hours • 5 Cycles
hotel
01:30 AM
6 Hours • 4 Cycles
Note: This calculator assumes it takes the average person 14 minutes to fall asleep.
The Science of Sleep Cycles
Sleep is not a uniform state of rest. Instead, your brain cycles through distinct phases roughly every 90 minutes. Waking up at the end of a cycle, rather than in the middle of deep sleep, is the secret to feeling refreshed.
light_mode
Light Sleep
The transition between wakefulness and sleep. Easy to wake up, but vital for memory consolidation.
dark_mode
Deep Sleep
When the body repairs itself and regrows tissue. Waking up here causes "sleep inertia" or grogginess.
psychology
REM Phase
Rapid Eye Movement. This is where most dreaming occurs and your brain processes emotions.