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Check if a website supports HTTP/2 and HTTP/3 protocols.
Modern protocols like HTTP/2 and HTTP/3 provide faster, more secure connections. Find out if your favorite websites support them.
Simply paste any website URL into the checker above. Our tool works with any publicly accessible website on the internet.
We perform live protocol negotiation with the target server to detect actual HTTP/2 and HTTP/3 support in real-world conditions.
Get detailed results showing which protocols are supported, with clear indicators for HTTP/1.1, HTTP/2, and HTTP/3 compatibility.
Performance improvements that make a difference
HTTP/2 revolutionized web performance by allowing multiple requests over a single connection, compressing headers, and enabling server push. It's widely supported and offers significant speed improvements over HTTP/1.1.
HTTP/3 takes it further by using QUIC (Quick UDP Internet Connections) instead of TCP. This eliminates head-of-line blocking, reduces connection setup time, and performs better on mobile and unreliable networks. It's the future of web protocols.
Real-time data from Cloudflare (Last 7 days)
Updated: Nov 30, 2025
Legacy protocol still in use
Most widely adopted modern protocol
Next-generation protocol, rapidly growing
Legacy support
Mature & stable
Fast adoption