Attenuation, to a brewer or vintner, is the percentage that measures the conversion of sugars into alcohol and carbon dioxide by the fermentation process.

Attenuation can be calculated using this formula:

(Starting Gravity - Final Gravity / Starting Gravity-1) = Attenuation

Example: (1.061 - 1.010) / (1.061 - 1) = 0.83 or 83% Attenuation