Online Beer Calculator Off - ??

Hey,

I've been using Hopville's online calculator and it's not giving me correct ABV's.

A year ago, I bought a kit from my LHBS. The label said it was 5.2% abv. I double checked it against Hopville and it almost spot on.

Now, the calculator now says that it has a lower abv.

Here is my fermentables:
6lbs LME
1lbs Crystal 150
.25 Belgian Special B
.25 Roasted Barley

S-04 Yeast.

It's supposed to be 5.2% abv. The calculator now says it is 4.5%

Thoughts feedback. Maybe someone can help me by double checking it against another calculator.

Thanks,
E

After posting this thread, I clicked on the "Similar Threads" links at the bottom and found a few other online calculators.

This one seems to be closer http://www.brewology101.com/AleAbacus#

It's showing that it's 5% abv.

Thanks
E

What do you assume for your final volume? Using my default settings, I get 4.7-4.8% ABV for a 5.5 gallon batch, 5-5.3 for a 5 gallon batch.

The variation depends on assumptions about post-boil volume losses.

zeg said:

What do you assume for your final volume? Using my default settings, I get 4.7-4.8% ABV for a 5.5 gallon batch, 5-5.3 for a 5 gallon batch.

The variation depends on assumptions about post-boil volume losses.

Click to expand...

I am doing 5 gallons for my final volume.

Did you run it through Beer Smith? Your target abv's look close to what I used to get using Hopville.

I'm on a Mac. From what I can remember, Beer Smith does not run on a Mac.

Thanks,
E

(OG-FG)*131=ABV

Pretty simple if you have your OG and your FG regardless what the recipe states. If your starting and finished gravities were different then then so too will be your ABV

BeerSmith 2 runs on my Mac just fine. It's what I used, but duboman's formula is find up to ABV around 10%. Above that it can underestimate by a bit. (I don't know whether BeerSmith uses a more sophisticated model or not.)

It will also vary on the brewing efficiency you put into the calculator so you may need to double check that it is correct or closer to correct.

Yeah, though since the majority of the gravity comes from extract, efficiency shouldn't make a big difference except through volume losses.

Nightshade said:

It will also vary on the brewing efficiency you put into the calculator so you may need to double check that it is correct or closer to correct.

Click to expand...

Only if discussing estimated ABV.

The equation I mentioned will tell you what your ABV is as determined by knowing the actual FG and OG of your beer.

duboman said:

Only if discussing estimated ABV.

The equation I mentioned will tell you what your ABV is as determined by knowing the actual FG and OG of your beer.

Click to expand...

My bad, I missed that part of this conversation...carry on