The BAC Calculator

LABEL-READING TOOL

ABV to proof.
One U.S. label conversion.

Convert alcohol by volume and U.S. proof. The conversion explains a label's strength; you still need the serving or container size to estimate how much alcohol is in a drink.

ABV & PROOF CONVERTER

What does this label value mean?

Enter one value

This converts label notation only. It does not measure alcohol in a serving or impairment.

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Strength × volume
is what matters.

A 40% ABV spirit is 80 proof in the U.S. But total alcohol still depends on how much is poured. Pair this converter with a serving or container calculation.

Calculate pure alcohol grams
Calculate a full container
Read what ABV means

How U.S. proof and ABV relate

For the U.S. convention used here, proof = ABV × 2. To reverse it, divide U.S. proof by two. For example, 40% ABV converts to 80 proof, and 100 proof converts to 50% ABV.

Read the label first

Proof does not tell you how much alcohol is in a serving on its own. Use the product's volume together with ABV. The standard drinks calculator is for a serving; standard drinks per container is for a full bottle or can; and standard drinks in spirits and shots explains common pour examples.

Proof and ABV are label-strength measures, not impairment measures. Do not use them to decide whether to drive, operate equipment, or make a medical or legal decision.

Where this conversion applies

Proof conventions vary by market. This calculator intentionally uses the U.S. relationship only. If your label already shows ABV, enter that figure directly into a serving or container tool instead of converting it.

Sources and review

  1. U.S. TTB: distilled spirits alcohol-content labeling
  2. The BAC Calculator: what ABV means

Last reviewed: July 23, 2026 · Read our editorial policy.