There are 2 calculations to determine the strength as long as you have a hydrometer.
ABV= OG - FG / .00738
Original gravity minus final gravity divided by .00738
- O.G 1.036 -
- F.G 1.003
- = 4.5 % (once rounded up/down)
- OG - FG * 131
- .036 - .003 = .04 x 131 = 4.5
Using 135 instead of 131 I think takes into account the priming sugars.
Will be back tomorrow posting about knitting again, I'm also playing with the layout of the blog and stuff . It may appear broken at times but don't worry I've not fallen into the bucket of homebrew.