What Is HTTP/3? Why Most of the Web Still Isn't Using It

Every major browser decided HTTP/3 was ready years ago. Chrome, Edge, Firefox and Safari have all shipped full support since 2022, and caniuse.com puts global browser support at 94.55% as of October 2026. Yet according to W3Techs, only 40.8% of websites actually served pages over HTTP/3 as of October 2026. That gap, not the protocol itself, is the real HTTP/3 story: browsers have been ready for years, and most servers still are not. Key takeaways Browser support for HTTP/3 sits at 94.55% globally (caniuse.com, October 2026), but only 40.8% of websites actually serve traffic over it (W3Techs, O