Use this to understand how different versions of efficiency work. Using any units will work here as the calculator is working out percentages.

Mash efficiency is how efficiently your mash was converted. This will usually be calculated from the grains and volumes in your recipe. This is the primary efficiency figure Brewbat uses in it's recipes.

Brewhouse efficiency is mash efficiency less vessel loss. Unless there is no vessel loss, this figure will always be lower than mash efficiency.

Complete mash or brewhouse efficiency to obtain your conversion.