A device and a method for calibrating a sensor, e.g., a force sensor such as a belt-force sensor, which allow reliable calibration of the sensor in a simple manner to counteract age-related distortion of measured values. The device for calibrating a sensor includes an arrangement for detecting at least one defined state of the sensor. When the sensor is in a defined state thusly detected, a corresponding adjustment of the measured value of the sensor may be implemented within the framework of the method.