Sleep Debt & Circadian Cycle Calculator
Calculate optimal bedtimes based on 90-minute natural REM sleep cycles and track sleep debt.
â° Wake-Up Parameters
đ Suggested Bedtimes (Wake at 07:00)
Waking at the end of a 90-min cycle prevents morning grogginess (sleep inertia).
About Sleep Debt & Circadian Cycle Calculator
Wake up energized and eliminate chronic daytime fatigue with our Sleep Debt & Circadian Cycle Calculator. Calculates your accumulated sleep debt over the past week and maps 90-minute natural REM sleep cycles to determine your exact optimal bedtime.
Sleep Calculator Features
- đ 90-Minute REM Cycle Mapping: Avoid waking up mid-deep sleep grogginess (sleep inertia).
- đ¤ Sleep Debt Accumulation: Quantify total lost sleep hours and get a healthy catch-up schedule.
- â° Dual Calculation Modes: Calculate when to fall asleep if waking at X time, or when to wake up if going to bed now.
- đ§ Circadian Rhythm Tips: Science-backed recommendations on light exposure and melatonin timing.
How to Calculate Your Sleep Cycles
- Enter your target wake-up time in the morning.
- Add average minutes it takes you to fall asleep (default 15 mins).
- Review the suggested bedtimes corresponding to 5 or 6 complete REM cycles (7.5 to 9 hours).
- Set your alarm to complete full 90-minute cycles.
Frequently Asked Questions (FAQ)
Why are 90-minute sleep cycles important?
A standard human sleep cycle consists of Light Sleep, Deep Slow-Wave Sleep, and REM sleep lasting ~90 minutes. Waking up at the end of a cycle ensures you feel alert and refreshed.
Can you pay off sleep debt in one night?
No, repaying sleep debt is best done gradually by adding 30-60 minutes of extra sleep per night over several days.
Is this sleep calculator free?
Yes, it is 100% free with customizable sleep latency.
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