#### fermenator

##### Well-Known Member

- Joined
- Jun 15, 2007

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I used a refracto for my last batch and have a question regarding the conversions. I use the MoreBeer spreadsheet (found here: http://morebeer.com/public/beer/refractbeer.xls)

to convert from Brix to SG and FG.

SG converts from 16.5 brix to 1.064

FG converts from 8 brix to 1.011

This is using the temp correction column as it should be for my ATC refracto.

However if you do the simple math converstion (16.5 x 4 = 64 which = 1.064) for the starting gravity, it works out the same. But if you so the same math for the FG it works out to be (8 x 4 = 32 which = 1.032) which is obviously too high of a gravity reading for a completed fermentation. I know fermentation is complete because I also took hydrometer readings which resulted in matching the spreadsheet values.

I am just confused on the differences between the "simple" math and the spreadsheet. The spreadsheet obviously counts for F.G. adjusted for Alc and Temp and I was wondering what the math was here in order to understand it more. I looked at the formula in excel but its a bit complex and I was hoping for a simpler explanation.

Thanks!