How to Use a Hydrometer to measure ABV

Your Hydrometer is an instrument that allows you to calculate the alcohol by volume (ABV) of your finished bee to that you can tell people what % alcohol beer they are drinking, especially when having a Belgian Home Brewed Beer. And to Identify whether your beer has finished fermenting and ready to be bottled.

To measure your ABV. A gravity reading must be taken before the start of fermentation and is called the Original Gravity (OG) Make sure to take the reading when your wort has cooled down and before pitching your yeast.

Another gravity reading is taken at the end of the brewing process and this is called the Specific Gravity (SG) These two readings are added and subtracted to give you an approximate alcohol reading.

Start the process by filling the cylinder ¾ full of wort from the fermenter and place the hydrometer inside. Give the hydrometer a spin to get rid of any bubbles and allow it to settle.

Record the number on the hydrometer where the wort crosses the line. In the picture, you can see that the (OG) reading of this beer was 1.060.

Do not put the wort sample into the fermenter after taking the reading as this will contaminate your wort.

When your beer has finished fermenting and it is time to bottle, you’ll need to take a (SG) reading. Follow the same steps as above. As you can see from the picture it ended up with a Final Gravity of 1.010

Now you should have your reading for your (OG) and your reading for your (SG) recorded in your notes.

To calculate ABV, subtract the (OG) from the (SG) and multiply by 131.25. As below.

(OG-SG) x 131.25 = ABV

Using the formula provided I can now calculate my ABV:

(1.060-1.010) x131.25 = 6.56%

Record your ABV and share with friends and family.

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