A method and a device for determining motion parameters of a conductive, profiled surface (22) relative to a sensor (3), with the sensor (3) comprising at least one coil for generating an electromagnetic alternating field, which is subjected, because of the feedback resulting from position changes between the surface (22) and the sensor (3), to a variation, which is determined by means of the coil (16). The position change is derived from the coupling impedance (Z.sub.c) of the coil (16), and the real component (R.sub.c) and the imaginary component (X.sub.c) of the complex coupling impedance (Z.sub.c) of the coil (16) are determined, with a distance d between the sensor (3) and the surface (22) being computed based on the determined values while using an algorithm as a basis.