Method for measuring vibrations of a vibrating machine, in particular a vibrating screen or a vibrating conveyor, during operation, in which the vibrating machine vibrates at an excitation frequency predetermined by a vibrating drive, with a vibration sensor which detects vibration components (S_x, S_y, S_z) of the vibrations of the vibrating machine in three spatial directions of a Cartesian sensor coordinate system (kl), wherein the three vibration components (S_x, S_y, S_z) form a vibration vector and the following steps are carried out: - determining a gravitational vector which describes the gravitational direction, wherein the gravitational vector is determined as the time average of the vibrations (S_x, S_y, S_z) of the vibrating machine detected by the vibration sensor, wherein the vibration signals (S_x, S_y, S_z) are rounded to an integer number of the periods of the excitation frequency, - determining a machine vector which describes a preferred direction of an imposed vibration of the vibrating machine, wherein the vibrations (S_x, S_y, S_z) are converted into the Fourier space by a Fast Fourier transformation in order to determine the machine vector, and the amplitudes, determined there, of the vibrations of an excitation frequency specified by the vibrating machine form an amplitude vector which points in the preferred direction, - forming a three-dimensional Cartesian measurement coordinate system which is aligned on the basis of the gravitational direction and the preferred direction, wherein a first axis of the measurement coordinate system extends parallel or antiparallel to the gravitational vector and a second axis of the measurement coordinate system extends along the portion of the machine vector which is orthogonal to the first axis, or a first axis of the measurement coordinate system extends parallel or antiparallel to the machine vector and a second axis of the measurement coordinate system extends along the portion of the gravitational vector which is orthogonal to the first axis, and - mapping the vibration vector from the sensor coordinate system into the measurement coordinate system. with a vibration sensor which detects vibration components (S_x, S_y, S_z) of the vibrations of the vibrating machine in three spatial directions of a Cartesian sensor coordinate system (kl), wherein the three vibration components (S_x, S_y, S_z) form a vibration vector and the following steps are carried out: - determining a gravitational vector which describes the gravitational direction, wherein the gravitational vector is determined as the time average of the vibrations (S_x, S_y, S_z) of the vibrating machine detected by the vibration sensor, wherein the vibration signals (S_x, S_y, S_z) are rounded to an integer number of the periods of the excitation frequency, - determining a machine vector which describes a preferred direction of an imposed vibration of the vibrating machine, wherein the vibrations (S_x, S_y, S_z) are converted into the Fourier space by a Fast Fourier transformation in order to determine the machine vector, and the amplitudes, determined there, of the vibrations of an excitation frequency specified by the vibrating machine form an amplitude vector which points in the preferred direction, - forming a three-dimensional Cartesian measurement coordinate system which is aligned on the basis of the gravitational direction and the preferred direction, wherein a first axis of the measurement coordinate system extends parallel or antiparallel to the gravitational vector and a second axis of the measurement coordinate system extends along the portion of the machine vector which is orthogonal to the first axis, or a first axis of the measurement coordinate system extends parallel or antiparallel to the machine vector and a second axis of the measurement coordinate system extends along the portion of the gravitational vector which is orthogonal to the first axis, and - mapping the vibration vector from the sensor coordinate system into the measurement coordinate system. - determining a gravitational vector which describes the gravitational direction, wherein the gravitational vector is determined as the time average of the vibrations (S_x, S_y, S_z) of the vibrating machine detected by the vibration sensor, wherein the vibration signals (S_x, S_y, S_z) are rounded to an integer number of the periods of the excitation frequency, - determining a machine vector which describes a preferred direction of an imposed vibration of the vibrating machine, wherein the vibrations (S_x, S_y, S_z) are converted into the Fourier space by a Fast Fourier transformation in order to determine the machine vector, and the amplitudes, determined there, of the vibrations of an excitation frequency specified by the vibrating machine form an amplitude vector which points in the preferred direction, - forming a three-dimensional Cartesian measurement coordinate system which is aligned on the basis of the gravitational direction and the preferred direction, wherein a first axis of the measurement coordinate system extends parallel or antiparallel to the gravitational vector and a second axis of the measurement coordinate system extends along the portion of the machine vector which is orthogonal to the first axis, or a first axis of the measurement coordinate system extends parallel or antiparallel to the machine vector and a second axis of the measurement coordinate system extends along the portion of the gravitational vector which is orthogonal to the first axis, and - mapping the vibration vector from the sensor coordinate system into the measurement coordinate system.