The effect of eddy currents and ferromagnetic resonance (FMR) on the frequency dependence of the permeability of FeTaN thin films is studied. An equation is given that describes the combination of these two effects. The agreement between the theoretical calculations and the experimental data is excellent. Already at 1 MHz the imaginary part of the permeability is significantly changed by FMR. Above 10 MHz the real part of the permeability is decreased by FMR. The combined effect is best observed in extremely high permeable, 1 &mgr;m thick films. A value for the ferromagnetic damping constant is obtained. ©1997 American Institute of Physics.