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Sleep Calculator

Wake up feeling rested — at the end of a natural cycle.

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Recommended bedtimes

  • minimal
    4 cycles6h
    Go to sleep at12:45 AM
  • solid
    5 cycles7h 30m
    Go to sleep at11:15 PM
  • optimal
    6 cycles9h
    Go to sleep at9:45 PM

Sleep architecture · 5 × 90 min cycles

Light
Deep
REM

Waking at the end of a cycle means lighter sleep — less grogginess, more energy.

Sleep Science

Evidence-backed habits that compound over time.

Morning Ritual

Wait 90 Minutes for Coffee

Cortisol peaks right after waking — adding caffeine then doubles the stimulants and deepens the crash that follows. Wait 90 minutes and let caffeine kick in right as your natural alertness starts to fade.

Morning Ritual

15 Minutes of Morning Sun

Within 30 minutes of waking, get 15 min of direct sunlight. It sets a biological timer that triggers melatonin production exactly 14–16 hours later, syncing your body clock automatically.

Wind-Down

The 3-2-1 Rule

Count back from bedtime:

  • No more food — digestion raises core temp and blocks deep sleep
  • No more work — stops the cortisol loop and brain-spin
  • No more screens — blue light suppresses melatonin
Consistency

Same Wake Time Beats 8 Hours

Waking at the same time daily, including weekends, is more important for brain health than total sleep hours. The "8-hour rule" misses the point. Your body runs on regularity, not arithmetic. Besides, your body will tell you to sleep earlier if you haven't gotten enough sleep the night before.

Quick Fix

The Coffee Nap

If you're tired in the middle of the day, drink a black coffee, then immediately take a 25-minute nap. While you sleep, adenosine (the fatigue chemical) clears. Caffeine absorbs and blocks new adenosine right as you wake, giving you ~4 hours of energy.

Environment

The 5-Sense Bedroom

  • Sight: dim lights 30 min before bed; total darkness to sleep
  • Sound: silence or white noise; avoid emotionally charged audio
  • Temp: 65–68°F (18–20°C)
  • Smell: lavender or ylang-ylang in a diffuser (not candles)
  • Touch: sleeping naked aids thermoregulation; socks help to warm up initially
Environment

Sleeping position pillows

  • Side sleeper: firm + high — keep your nose aligned with your sternum. Pillow between legs to align spine
  • Back sleeper: medium support under the neck
  • Stomach sleeper: Low pillow + pelvic pillow to help mitigate issues. Best to force yourself to change positions as it causes bad spinal strain
  • Material: skip polyester (traps heat); look for adjustable fill
Waking at Night

Why You Wake at 3AM

75% of sleep problems are psychological. When it happens, avoid these:

  • Checking the clock — it triggers anxiety and makes it worse
  • Grabbing your phone — blue light kills melatonin fast
  • Lying there frustrated — get up, do something calm in low light and return when sleepy