Binary fractional distillation is a means of separating two liquid components via a distillation column (which contains a number of trays, or stages). It's a concept encountered by virtually every Chemical & Process Engineering student. This application calculates the required number of theoretical stages for a set of specified operating parameters via the McCabe-Thiele method. It plots the classic McCabe-Thiele diagram and evaluates the minimum and actual reflux ratio, and the thermodynamic state of the feed.