Size segregation of polydisperse materials during hopper discharge is problematic in various industrial situations. However, due to the complexity of hopper discharge flow kinematics and limited prediction techniques for polydisperse segregation, accurate modeling of polydisperse segregation during hopper discharge has been challenging. We extend the application of a general predictive continuum model that captures the effects of segregation, diffusion, and advection to polydisperse hopper flow. Model predictions of segregation within the hopper and the average particle diameter during discharge match experimentally validated discrete element method simulations and experiments. (C) 2020 Published by Elsevier B.V.