How does Alcohol percentage work?

Question

Trying to figure this out, I drank an 8% Stout. Is this the same as drinking two 4% beers or am I stupid?

Quick edit: I drink three 8% stouts, I assume this is the equivalent of six 4% beers of the same volume?

In: 3

Answer 1

That’s correct.

The alcohol percentage given on a bottle indicates the volume of the drink that is alcohol. So, a 100 mL bottle with alcohol percentage 8% contains 8mL alcohol. That’s the same as drinking two 100 mL bottles of a 4% drink, which each contain 4 mL alcohol. Note that this only works out to the same amount of alcohol if the bottles are all the same total volume (100 mL).

So as you say, if the bottles are all the same volume, three 8% bottles contain contain the same amount of alcohol as six 4% bottles.