A method is described whereby the permeability of soft magnetic laminations can be calculated from a material permeability of different dependences on field strength. Computer-aided solutions are given for typical laminations, magnetic qualities, and rise functions of material permeability. The results are compared with those calculated using an earlier theory based on a field-strength-independent material permeability. Limits in permeability rise are derived up to which the latter method can be used with tolerable differences. The extended method may further be used at higher flux densities, including cases of magnetic anisotropy.