A free program for the simulation of dynamic infrared (IR) spectra is presented. The program simulates the spectrum of two exchanging IR peaks based on simple input parameters. Larger systems can be simulated with minor modifications. The program is available as an executable program for PCs or can be run in MATLAB on any operating system. Source code is also provided to encourage computer coding projects based on the program. The program is useful for upper-division undergraduates and demonstrates several important concepts from physical chemistry. Example exercises based on the program are included.