A method for calibrating a cleaning device that has at least one sensor for detecting at least one state variable, including carrying out a calibration measurement, establishing an electronic connection between the calibration sensor and a controller of the cleaning device, and electronically transmitting the reference value to the controller; and comparing the reference value with at least one measurement value of the sensor of the cleaning device and adjusting at least one correction function in accordance with the comparison. At least one state variable is detected and at least one reference value is determined by means of at least one calibration sensor independently of the sensor of the cleaning device. Future measurement values of the sensor of the cleaning device are automatically corrected using the correction function.