We used bi-axial VSM to evaluate the anisotropy dispersion of a rotational-field-annealed CoZrNb thin film that shows an almost isotropic M-H curve. It was demonstrated that the isotropic properties of this film resulted from wideangle dispersion of the anisotropy. Using the measured Hk of the film, we calculated the frequency dependence of the permeability, and found that the calculated value agrees well with the measured one. We also calculated the magnetic torque curve, using the measured magnetic anisotropy dispersion of a CuMo-permalloy film. The calculated curve also agrees well with the measured curve.