A system determines an absolute tilt angle in relation to the horizontal, especially for use in a motor vehicle. The system includes at least one sensor element having a main axis of sensitivity and disposed such that its main axis of sensitivity lies in the plane of the tilt angle to be detected. The at least one sensor element produces a sensor signal depending on the tilt angle in relation to the horizontal. The sensor signal is a measured acceleration of the system. The system also includes a device for detecting an acceleration component of the measured acceleration and a processing unit to which the measured acceleration and the acceleration component are supplied in order to determine an acceleration component-corrected acceleration from which the absolute tilt angle of the system in relation to the horizontal can be determined.