Abstract: A method for automatically testing a website or a web application may include steps of examining the code of an opened Web page or Web application and detecting and categorizing user input fields in the examined code. A knowledge base of standard inputs that stores a plurality of categorized standard inputs may then be consulted. A standard input may then be selected from the knowledge base of standard inputs and applied to the detected input field. When the website or web application generates a message in response to the applied standard input, a knowledge base of standard errors that stores a plurality of standard errors may be consulted. The generated message may then be matched to one of the stored standard errors or a likelihood that the generated message is an error message may be assigned when the generated message does not match one of the stored standard errors.