Computer systems and methods for interfacing with a third party website, comprising determining that a webpage of the third party website is being output in an interface of a web browser, and in response, generating an interface element that at least partially overlaps the webpage in the interface. The interface element includes a user-selectable graphical trigger that, when selected, causes digital codes to be automatically input into a data entry interface identified in the webpage, thereby triggering the third party website to receive each of the digital codes and to return a respective response. Based on monitoring the respective response to each of the digital codes, a particular digital code is identified that causes a greatest change in a numerical value displayed in the webpage. The particular digital code is applied to obtain a resulting numerical value that is displayed in the webpage.