A method of adjusting a quantization accuracy of a fill level radar for detecting a fill level of a container is provided, the method including the steps of: acquiring amplitude values of an echo curve of the fill level radar by an analog-to-digital converter (ADC); determining a first amplitude value of a first echo having a highest amplitude or a highest local amplitude maximum of the echo curve; determining a second amplitude value of a second echo having a lowest local amplitude maximum of the echo curve; setting an adjusted quantization accuracy as a function of a quotient of the first amplitude value and the second amplitude value; and determining the fill level of the container with the adjusted quantization accuracy. A field device including a fill level radar and/or an ultrasonic measuring device configured to perform the method is also provided.