Abstract: To provide a measuring method on an electric motor with a rotor and a stator for determining the fly height and/or axial play, the rotor being mounted, and in particular fluid-mounted, on the stator, with which method the axial position of the rotor in relation to the stator can be determined with high levels of accuracy and reproducibility, it is provided that the electric motor is operated at a defined measuring speed, at which the rotor is in a specific axial position in relation to the stator, with this relative axial position being determined in that the rotor is brought in a defined manner, with the motor at a standstill, into a first stop position in relation to the stator, in that the rotor is brought in a defined manner, with the motor at a standstill, into a second stop position in relation to the stator, lying opposite the first stop position, and in that the relative axial position between the rotor and the stator is respectively measured in the two stop positions.