Here is a calculator that will tell you how many cups, or glasses of any size, you will get out of a quarter or a half keg of beer. Just enter in the size of the cup you will be using cup using and then check the size of the keg. (half or quarter) Then click "Click Here To Calculate Number of Cups". That's it! No more guessing if you will have enough beer for everybody and no more (heaven forbid) wasting beer!