Methods and apparatus, including computer systems and program products, for creating and using documents with machine-readable codes. A computer program displays a list of fields in an electronic document, receives user input selecting one or more of the fields, automatically generates generation instructions for a machine-readable code to be displayed in a final appearance of the electronic document, and stores the generation instructions in the electronic document. The generation instructions specify that the machine-readable code is to be produced using data to be provided for the selected fields. In some embodiments, the program can also evaluate the user input, as well as user modifications made to the electronic document, to determine whether the machine-readable code is validly configured. By guiding users through the process of setting up machine-readable codes, the program can help users create forms with machine-readable codes that have a high probability of being scanned and decoded successfully.