Distillery calculation guide

How to Calculate Proof Gallons

A concise guide to the US proof-gallon calculation.

Working method

This guide uses the same verified calculation engine as the corresponding Stillbench bench tool. Keep units consistent, use measured values, and treat the result as a production-planning estimate.

Verify before production

Temperature, instrument calibration, alcohol-volume contraction, local reporting rules, and operating conditions can affect production measurements. Verify the result using the procedures appropriate to your operation.