Beer Forum

I recently purchased a refractometer, and it has been a great tool for preboil and OG readings. However, when it came down to taking FG, the reading was way high after 2 weeks in the primary. OG was 1.071, and refrac read 1.030ish for FG. I was curious so went to me hydrometer and that read at 1.008. I understand that fermented beer has alcohol and that changes the way a refrac works. However, is there a way to measure FG with the refrac and quickly convert it, or do I need to stick to taking hydrometer samples to remain quick and easy?

LostBoy wrote:I recently purchased a refractometer, and it has been a great tool for preboil and OG readings. However, when it came down to taking FG, the reading was way high after 2 weeks in the primary. OG was 1.071, and refrac read 1.030ish for FG. I was curious so went to me hydrometer and that read at 1.008. I understand that fermented beer has alcohol and that changes the way a refrac works. However, is there a way to measure FG with the refrac and quickly convert it, or do I need to stick to taking hydrometer samples to remain quick and easy?

More beer has a refractometer Alcohol Correction Spreadsheet you can download.

I use the BrewMath app on my iPhone for that.

Promash and Beersmith also do the math for you.