Alcohol Blending (Proof Gallons) Calculator

Work out alcohol blending (proof gallons) instantly with clear inputs, formula shown and shareable results.

About Alcohol Blending (Proof Gallons) Calculator

A proof gallon is one US gallon at 100 degrees proof, which is 50% alcohol by volume. Proof gallons equal wine gallons times proof divided by 100, and excise duty is assessed on proof gallons. Gauging must be corrected to the reference temperature of 60 F using the official tables.

Formulas

Proof gallons

Proof gallons = wine gallons x proof / 100

Proof and ABV

ABV % = proof / 2 (US convention)

Worked example

With the default values below, Alcohol Blending (Proof Gallons) Calculator returns Proof Gallons of 80.0000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Volumeminimum 0 US gallons: 100 US gallons
Proofaccepts 0–200 degrees proof: 80 degrees proof
Temperatureminimum 0 degrees F: 60 degrees F
Duty Rateminimum 0 per proof gallon: 13.5 per proof gallon

Results

Proof Gallons: 80.0000
Alcohol By Volume: 40.000%
Duty Payable: $1,080.00
Gauging Note: At reference temperature

Step by step

1Values used
2Proof gallons
3Proof and ABV
4Proof Gallons= 80.0000
5Alcohol By Volume= 40.000
6Duty Payable= 1,080.00
7Gauging Note= At reference temperature

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Excise gauging and duty calculation must follow the official tables and procedures of the tax authority. Errors in proof gallon determination create duty liabilities and penalties.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Excise gauging and duty calculation must follow the official tables and procedures of the tax authority. Errors in proof gallon determination create duty liabilities and penalties.

Frequently Asked Questions

What is a wine gallon?

Simply a gallon of liquid volume regardless of strength, as opposed to a proof gallon which is volume adjusted for alcohol content. Duty is on proof gallons, inventory is often in wine gallons.

Is proof the same everywhere?

No. US proof is twice ABV. Historical UK proof was different, with 100 degrees proof equal to 57.15% ABV, and the UK now uses ABV directly. Always state the convention.