Estimate blood alcohol concentration from drinks consumed, body weight, and time elapsed. Educational estimate only.
In the US, a standard drink contains about 14 grams of pure alcohol — roughly a 12 oz beer at 5% ABV, a 5 oz glass of wine at 12% ABV, or a 1.5 oz shot of 40%-ABV liquor. Stronger or larger pours count as more than one standard drink.
This uses the classic Widmark equation: BAC = (alcohol grams ÷ (body weight in grams × distribution ratio)) × 100, then subtracts an elimination rate of about 0.015% per hour to account for metabolism since your first drink. The distribution ratio (about 0.68 for men, 0.55 for women) reflects average differences in body water content, which affects how diluted the alcohol becomes.
In the US, 0.08% is the standard legal limit for drivers 21+, with stricter limits for commercial drivers and those under 21. Limits vary by country and jurisdiction — and impairment can begin well below any legal limit.
Yes — food slows alcohol absorption, and BAC only decreases once your liver has had time to metabolize the alcohol, at a fairly constant rate over time. Neither coffee nor a cold shower speeds this up.
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