A physics-based impedance model of a proton exchange membrane fuel cell is developed, incorporating a coupled oxide growth-oxygen reduction reaction kinetic model. The oxide layer is shown to produce a low frequency inductive loop that agrees quantitatively with the experimental inductive loop at current densities as high as 800 mA/cm(2), even when kinetic and mass-transfer parameters are fit from polarization curves and cyclic voltammetry instead of electrochemical impedance spectroscopy. The importance of the inductive loop in explaining both AC and DC results is discussed. (C) The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. All rights reserved.