This paper describes the design, implementation, and initial evaluation of WebVizOr, an open-source tool that enables visualization and comparative analysis of test results from web applications. Because of its embedded framework, testers can automatically utilize any of a set of available test oracles. Using WebVizOr can (1) eliminate much of a human tester’s laborious and error-prone manual analysis and (2) direct the development of new test oracles, thus improving the quality of the testing process and ultimately web application reliability.