Understanding your sleep cycles can help you wake up feeling more refreshed and energized. This calculator uses the average 90-minute sleep cycle to suggest optimal bedtimes or wake-up times.
Most adults need between 7-9 hours of sleep per night, which typically translates to 5 or 6 full 90-minute sleep cycles. Waking up at the end of a sleep cycle, rather than in the middle, can prevent that groggy feeling often associated with your alarm clock.
Calculate Your Ideal Bedtime
Enter your desired wake-up time and how long it typically takes you to fall asleep. The calculator will suggest bedtimes that allow you to wake up at the end of a sleep cycle.
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Calculate Your Ideal Wake-up Time
If you're going to bed now (or at a specific time), enter that time and how long it typically takes you to fall asleep. The calculator will suggest wake-up times that allow you to complete full sleep cycles.
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Understanding Sleep Cycles
A typical sleep cycle lasts about 90 minutes and consists of several stages: NREM (Non-Rapid Eye Movement) stages 1, 2, and 3, followed by REM (Rapid Eye Movement) sleep. Waking up during NREM stage 1 or 2, or at the end of a REM cycle, often feels more natural than being jolted awake during deep sleep (NREM stage 3).
NREM Stage 1: Light sleep, easy to wake up.
NREM Stage 2: Deeper sleep, body temperature drops, heart rate slows.
NREM Stage 3: Deepest sleep, crucial for physical restoration and growth. Waking up here can cause grogginess.
REM Sleep: Brain activity increases, vivid dreams occur. Important for cognitive functions and emotional processing.
By aiming to wake up after completing a full 90-minute cycle, you're more likely to emerge from a lighter stage of sleep, leading to a more pleasant and less disorienting awakening.
Tips for Better Sleep Hygiene
Maintain a Consistent Schedule: Go to bed and wake up at the same time every day, even on weekends.
Create a Relaxing Bedtime Routine: Take a warm bath, read a book, or listen to calming music.
Optimize Your Sleep Environment: Keep your bedroom dark, quiet, and cool.
Limit Screen Time Before Bed: The blue light emitted from screens can interfere with melatonin production.
Watch Your Diet: Avoid heavy meals, caffeine, and alcohol close to bedtime.
Regular Exercise: Physical activity can improve sleep quality, but avoid intense workouts too close to bedtime.