What is HTTP/2 Checker?
HTTP/2 is the second major revision of the HTTP protocol, standardized in RFC 7540. It addresses key performance limitations of HTTP/1.1 by allowing multiple requests and responses to be multiplexed over a single TCP connection, eliminating head-of-line blocking. HTTP/2 also uses HPACK header compression to reduce overhead and supports server push to proactively send resources. HTTP/3, the latest version, replaces TCP with QUIC for even lower latency. Enabling HTTP/2 on a web server typically requires only a modern web server (nginx, Apache, Caddy) and a valid TLS certificate — and can improve page load speeds by 20–50% without any code changes.