The 1D active magnetic regenerator model developed at the University of Applied Sciences of Western Switzerland is described. The system of two partial differential equations is discretized with the finite differences method backward in time and solved with the tridiagonal matrix algorithm. New features, not found in the literature in 1D models, are thermal losses in the regenerator, parasitic heat exchange, and the calculation of the AMR cycle output power in steady state. The model is implemented in MATLAB and it has a graphical user interface.