WebPageTest
Unknown
Free real-browser performance testing tool recommended by practitioners
More resources on Web Performance
HTTP Archive
Data-driven insights into web performance trends
web.dev/performance
Official Google guide with free tools, audits, and best practices
Web.dev Learn - Performance
Learn web performance best practices with Google's web.dev course! Optimize your site for speed and a better user experience.
HTTP | Web Performance
Learn HTTP fundamentals & boost your website's speed! Barry Pollard's course unlocks key web performance optimization techniques.
High Performance Web Sites
High Performance Web Sites - A book resource
web.dev
web.dev is Google's hub for modern web development, focused on building fast, accessible, and reliable websites. It offers tutorials, guides, and tooling coverage on performance (Core Web Vitals), progressive web apps, accessibility, SEO, and other best-practice topics.