Performance profiling is a way of doing [[Frontend performance testing]] that involves running a tool that scores an application based on predefined criteria. Performance profiling is a good way to get an idea of how performant a site is initially, before tests are done. Profiling, however, does not provide a framework for testing an application directly-- only for measuring improvements quantitatively throughout the changes. ## Tools for performance profiling [[Chrome DevTools]] [[WebPageTest]] [[GTMetrix]] [[YSlow]] [[Google Lighthouse]]