The present disclosure relates to a system, method, and computer program for testing the accuracy of software that identifies user interface (UI) elements on a webpage (“the auto-identifier software”). The system enables a user to tag UI elements on a webpage with labels. The system creates a normalized specification for the webpage, where the specification includes a mapping of UI elements to normalized labels. The system uses the auto-identifier software to identify UI elements on the webpage. The system evaluates the performance of the auto-identifier software with respect to the webpage using the specification. The system displays diagnostics related to the performance of the auto-identifier software. In certain embodiments, the method is used for testing the accuracy of autofill software on a webform. In certain embodiments, the method is used for testing the accuracy of cart-scraper software on a checkout page.