How do you figure out the proof of a bottle of alcohol if the percentage is listed?

Question

and vise-versa.

Answer 1

the proof should be mon the bottle

korkie

Answer 2

Proof is two times the percentage

or the percentage is half the proof

so 75% would be 150 proof

or 100 proof is 50% alcohol

some alcohol has only the % listed, some has proof, some have both, some have neither.  There are no regulations on alcohol products for required labels like there are for standard food & drinks.