A method for determining a turbidity of a medium in a container using at least one turbidity sensor. Depending on the ambient conditions at the installation location of the turbidity sensor, comprising the following steps: passing transmitted radiation through the medium, wherein the transmitted radiation is converted by interaction with the medium, as a function of the turbidity in the received radiation; receiving the received radiation; converting the received radiation into a scattered light intensity, and determining the turbidity from the scattered light intensity. The method is characterized by the following steps: detecting the chronological sequence of the scattered light intensity; determining a mean value on the basis of the chronological sequence of the scattered light intensity; determining the turbidity from the mean value using a calibration model by assigning a turbidity to each mean value; determining a corrected mean value on the basis of the chronological sequence of the scattered light intensity, by determining a noise parameter from the scattered light intensity, and by determining the corrected mean value from the noise parameter using a noise model, and determining a corrected turbidity at least from the corrected mean value using the calibration model by assigning a corrected turbidity to each corrected mean value. The invention further relates to a turbidity sensor for implementing the method.