View Full Version : The all mighty ABV

11-17-2014, 04:38 PM
Hi all.
I'm fairly new to the brewing game, and as always being new brings up a lot of questions.

In wanting a good tasting brew we also want a to know the ABV whether that be a knock your socks off or a casual drink.

So my question is, what is (in your personal opinion) the best way to calculate the ABV of your brews?

Thanks in advanced


11-17-2014, 05:23 PM
The standard method is to get your starting and finishing gravity reading, shortened to SG and FG and subtract them to get your ABV. Something like this: Your SG is 1.110 and your FG is 1.005, your gravity drop would be 105. You then look up the relevant section in the NewBee guide here: http://www.gotmead.com/forum/showthread.php/22874-Newbee-Guide, or go to an ABV calculator, here is one: http://www.brewersfriend.com/abv-calculator/.

11-17-2014, 08:42 PM
As EMJ3 states. It's the change in gravity you're after.

An estimate can easily be calculated (for high alcohol brews like 12%+) using the magic approximate value of 135.
If the gravity drop is 0.105, multiply by 135 to get 14%
this will get you within plus/minus 0.5%

For brews below 12% you need a different magic number, which I don't recall, as I never make anything that light.

If you want a dry brew of 12% (which is equal to or less than your yeast tolerance) then simply divide 12/135 to get 0.089
So start your brew at 1.089.

This can also help you get a feel for residual sweetness, though that's a little bit of a gamble, as yeast never behave quite the way you expect.