Sleep Quality & Hours Calculator

About Sleep Cycles

Sleep occurs in cycles of about 90 minutes each, moving through light sleep, deep sleep, and REM (dream) sleep. Waking up at the end of a complete sleep cycle (after 6, 7.5, or 9 hours) helps you feel more refreshed than waking in the middle of deep sleep.

Sleep Quality Factors:

• Caffeine: Can stay in your system for 6-8 hours
• Alcohol: Disrupts sleep cycles even if it helps you fall asleep
• Blue light: From screens suppresses melatonin production
• Exercise: Regular exercise improves sleep, but intense workouts close to bedtime can be stimulating
• Stress: Activates your nervous system, making it harder to relax
• Consistency: Going to bed/waking at the same time regulates your circadian rhythm

Note: Most adults need 7-9 hours of sleep per night. This calculator provides general recommendations only.