In one example in accordance with the present disclosure, a method for assessing print quality is described. According to the method, a printed mark is converted into a digital binary mark. A number of values are calculated for the digital binary mark. The number of values include at least a perimeter length value and a value describing a characteristic of an intensity histogram for the digital binary mark. A combined representation of the number of values for the digital binary mark are compared against a combined representation of a number of values for a model printed mark. When the combined representation for the digital binary mark is greater than a predefined distance away from the combined representation for the model printed mark, an operation of a printing device that generated the printed mark is adjusted.