beer tools vs. beersmith, which is correct?

[cervid]

For the same recipe I get different IBU's, ABV, and SRM between the two. I adjusted the settings in beersmith to match what I have in beer tools now.

The IBU really confuses me because the same hops in beersmith at 4.8 comes out with less IBU's than in beer tools when they are at 4.5. Same schedule, of course.

What are others experiences with this?

 

[ShootsNRoots]

What formula are you using for IBU, Rager or Tinseth?

Boil volumes, batch size, late extract additions, hops AA etc... also affect IBU.

(4.8 and 4.5 refer to? ounces? grams?)

 

[cervid]

% of alpha acids. Like I said.. Everything is the same and the beersmith with .3% higher alpha acids is coming out with less IBU. I'm not using a formula, it's the default program settings. In the tools section of beersmith, when I change the hop bitterness formula, it doesn't change the recipe.

 

[cervid]

the terminal gravity calculation is totally different also.

 

[ShootsNRoots]

Want to have some real fun?

Put the recipe in Brewers Friend and get a third answer!

 

[Oginme]

I think the default calculation for bitterness in BeerSmith is Tinseth. You can also switch the calculation to Rager or Garetz. I don't know what beer tools uses.