Pre-boil gravity calculations.

General Homebrew Discussion
1

Alright, I know this wouldn’t be that hard to figure out…but my brain is failing me this morn.  What is the best way to figure approximate OG from my pre-boil SG?  Or…is there a calculator?

2

(SG*boil volume)/final volume=OG

3

Thank Denny, this is what I thought, but my math is really not working…I must be stu, stu, stupid today  ;D

So in my case I have:
(SG 1.040 * BV 6.5)/FV 5.5 = OG 1.229
This isn’t right.

4

I shoud have been more specific…you leave off the “1”, so it’s really ((SG-1)BV)/FV.  In your case it would be (406.5)/5.5=47.27

5

Yep, gravity points…not hydrometer readings, that’s what I was doing.

Thanks