'''Alcohol By Volume (ABV)''' is a measure of the percentage of alcohol volume over the total volume of the beer. This is equivalent to the ''proof'' value of higher alcohol liquors. Beer typically has an alcohol by volume value of between 3 and 8%. Barley wine may have an ABV as high as 10% or more. Note that while the majority of the world typically quotes alcohol by volume, in the US alcohol percentage is often measured as [[Alcohol By Weight]].
To calculate the approximate alcohol by volume, simply measure the original gravity [[Original Gravity]] and final gravity [[Final Gravity]] as a 3 digit [[specific gravity]] and apply this formula:
: '''ABV = (Orig_gravity - Final_gravity) * 131