This method for measuring the diameter of a circular track on a component comprises: a) a step (162) of moving the component along a measurement path, b) as the component is moving along the measurement path, a measurement step (170), for measuring at least one parameter, without contact with the component, c) a step (186) of determining the diameter of the circular track from the parameters measured. During step a) a robot continuously moves the component at an instantaneous speed that is never zero along the measurement path and an instantaneous acceleration that never changes sign along the measurement path.