Proof to ABV Converter
Convert between alcohol proof and ABV for US and UK scales by selecting the direction and system.
Verify labeling requirements with local regulations before bottling or selling spirits.
Examples
- 80 proof with mode 1 on the US scale ⇒ 40.00 % ABV
- 45% ABV with mode 2 on the UK scale ⇒ 78.75 proof
FAQ
Which proof system should I choose?
Select 1 for the modern US proof system or 2 for the historic UK proof degrees used on some spirits references.
Can I use decimal values?
Yes, enter fractional proof or ABV values for more precise conversions.
What happens if I pick the wrong mode?
The calculator will return the opposite unit, so ensure mode 1 is for proof to ABV and mode 2 is for ABV to proof.
Additional Information
- The United States defines proof as twice the ABV, while the historic UK scale multiplies ABV by 1.75.
- Use mode 1 to convert labeled proof to drinking strength, or mode 2 to estimate proof from a lab ABV result.