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Alcohol clearance calculator

One standard drink ≈ 14 g alcohol (12 oz beer, 5 oz wine, 1.5 oz spirits). Alcohol shortens REM and fragments the second half of sleep even when you feel “fine.” This uses a conservative buffer for sleep quality, not legal sobriety or driving.

For 2 drinks, a rough sleep-architecture buffer is about 4.25 h after the last sip (0.75 h base + 1.75 h × drinks).

Earliest “kinder to sleep” lights-out (same night): 00:15

Very rough subjective “clearing” curve (~2.3 h for low BAC) is faster — sleep still gets less REM. Women, low body weight, medications, and sleep apnea change this sharply.

Your target bedtime is earlier than this buffer.

Gap from last drink to bedtime ≈ 2.50 h (same calendar evening assumed).

Educational estimates only. Sleep and caffeine metabolism vary widely. This is not medical advice; talk to a clinician if you have insomnia, apnea, or other conditions.