### To measure the ABV for beer, you will first need to ensure you have the correct readings and then you can calculate the ABV.

- Take an SG reading using your hydrometer before fermenting (original gravity (OG)) (see reading SG below)
- Then another after the beer is ready to be bottled, (Final Gravity (FG)).

To calculate the percentage of beer, simply put your OG and FG into the following equation:

**ABV = (OG-FG) x 131**

**i.e.**

**ABV = (1.056-1.014) x 131**

**ABV = .042 x 131= 5.502%**

This is not an exact calculation as there are other factors involved. If the OG is lower, then the multiplier reduces. If calculating a beer with a start gravity of under 1030 then use 125 as a more appropriate multiplier.