The present invention relates to a method of determining an angle of a piece of working equipment of a machine, wherein the machine has an undercarriage and a superstructure rotatable with respect thereto, wherein the piece of working equipment is fastened to the superstructure via a swivel joint such that the angle of rotation of the swivel joint is orthogonal to the axis of rotation of the rotatable superstructure, wherein the piece of working equipment is provided with an IMU, that is in an inertial measurement unit, that is configured to detect an angular speed in three spatial directions that are preferably perpendicular to one another, and wherein a first of the three spatial directions, whose angular speed ({dot over (θ)}y) is detectable by the IMU is in parallel with the axis of rotation of the swivel joint. The method is characterised in that an angular speed ({dot over (θ)}tz) that occurs on a rotation of the superstructure is detected by the IMU and an angle of the piece of working equipment relative to the axis of rotation of the superstructure is determined on the basis of the detected angular speed ({dot over (θ)}tz) of the superstructure.