Understanding Blood Alcohol Content

What is a Standard Drink?

One standard drink contains 10g of pure alcohol. That equals: 330ml regular beer (5%), 100ml wine (13%), or 30ml spirits (40%). A large glass of wine or pint of strong beer is often 2+ standard drinks.

The Widmark Formula

BAC = (alcohol consumed in grams ÷ (weight in grams × distribution ratio)) − (elimination rate × hours). The distribution ratio is 0.68 for men and 0.55 for women. Elimination averages 0.015% per hour.

Important Disclaimer

This tool is for education only. Metabolism varies based on food consumption, medications, liver health, and genetics. The only safe BAC for driving is zero.

Blood Alcohol Content Calculator

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