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Estimated ABV vs Measured ABV

monsteroyd

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I customized a report to show the measured vs estimated values as follows:

Estimated OG: 1.041 SG
  Measured OG: 1.041 SG
Estimated FG: 1.003 SG
  Measured FG: 1.003 SG
Estimated ABV: 4.9 %
Measured ABV: 5.0 %

I am just curious as to why the estimated and the measured ABV are different. Not much different, but they should be equal. Rounding error? Are both values calculated with the same formula and / or rounding?

No biggy, but I noticed it so I thought I would mention it.

Oh I attached a jpg screenshot of the BS about dialog. Can't seem to insert it inline.

Monty

 

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A difference of 0.1 is well within an acceptable variation. Assuming you didn't change your recipe to fit the results, you're to be applauded for hitting your numbers so well.

BeerSmith's estimates have a lot of input to get to those estimates, so some rounding occurs because the actual number might go out 4 decimal places.

US labeling law allows breweries a variation of +/-0.2 from the stated abv. Just shopping the gravity numbers around to various online calculators yielded 4.9% to 5.2%.
 
Yes I understand that .1 is within error, however in this case, I was really just letting BeerSmith people know of the results. Obviously, the estimated OG and / or the estimated FG are not what is shown, and the measured are exactly what I entered because I don't have a higher resolution of measurement (more than 3 decimal places). But to me when I look at them both and I know the calculation is the same for either the estimated or measured, why does it show .1 difference? If you are going to print a rounded value, then you probably want to take the rounded value for the computation or you end up showing an obvious incorrect answer, as we can see.

Monty
 
Options > Units> Gravity Units.

You may increase the decimal resolution to your hearts' content.
 
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