1. An autofill system comprising: a trained machine learning component that uses one or more sets of inputs to facilitate autofilling a form field in a web-based form; and an autofill component that selectively enters data into the first form field and a second form field based at least in part upon information generated by the machine learning component, the information is generated as a function of a characteristic of at least a third field and includes a joint probability computed from a first probability that the data entered into the first form field is appropriate for the first form field and a second probability that the data entered into the second form field is appropriate for the second form field and wherein the data is consistent with one or more constraints, wherein the components are implemented with hardware.