Question 1

How accurate is a BAC calculator?

Accepted Answer

It's a physiology-textbook estimate (the Widmark formula), typically within ±0.02% of a breathalyzer under normal conditions, but food, medications, fatigue, and drink pours all move the number. Treat it as education, never as permission.

Question 2

What's one standard drink?

Accepted Answer

About 14 grams of alcohol: a 12oz beer at 5%, a 5oz glass of wine, or a 1.5oz shot of spirits. Craft beers, big wine pours, and cocktails often count as 1.5-2 standard drinks each, which is the most common reason people underestimate.

Question 3

How fast does BAC drop?

Accepted Answer

Roughly 0.015% per hour, and nothing accelerates it: not coffee, showers, or exercise. From 0.08% that's five to six hours to zero. Our sober-by-when page does this math for you.

Question 4

Can I drive if the calculator says I'm under the limit?

Accepted Answer

No. Impairment starts around 0.02%, estimates have real error bars, and a roadside test doesn't grade on effort. If you've been drinking at all, arrange another way home: that's the whole point of understanding these numbers.

BAC Calculator

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