Alcohol from Hydrometer & Refractometer
Details: This calculator uses a refractometer and hydrometer reading to ascertain the alcohol content of the sample. The gravity measurement must be from a hydrometer, and the °Brix measurement must be from a refractometer, these values must not have been calculated from one source.
Alcohol (ethanol) has a higher refractive index than water, so a dry wine will usually give a refractometer reading in the range 5 to 15°Brix.
This calculation uses the following formula:
alcohol by vol = 1.646 * b - 2.703 * (145 - 145 / s) - 1.794
Where:
b = °Brix reading (from refractometer)
s = specific gravity (from hydrometer)
VinoCalc by Jonathan Musther - jon@musther.net