This paper presents comparison of non-linear magnetic modelling techniques for an axial flux open slotted eddy current brake. Dynamic modelling of a designed axial flux open slotted eddy current brake having single rotor single stator is described. The magnetic and electrical properties of dynamic modelling which are effected the braking torque are explained. Magnetic modelling of a designed eddy current brake is investigated over one symmetrical flux path. Jakobi, Gauss-Siedel and Newton-Raphson non-linear modelling techniques are also examined. These techniques are explained and non-linear magnetic modelling flow chart is provided. Results obtained from non-linear modelling techniques are compared with 3-D finite element analysis and test results. Results show that Newton-Raphson method gives more reasonable result then Jakobi and Gauss-Siedel methods at high non-linear conditions.