Browser protocol
Navigation Timing reports the protocol used for this page, usually h2 for HTTP/2 or h3 for HTTP/3. Use Reload & check to measure a new page load.
Localtonet tools
HTTP/2 & HTTP/3 test
See the HTTP protocol your browser used to load this page.
Your result
Checking
Reading your connection…
Comparing browser navigation with the connection visible to Localtonet.
Browser protocolChecking…
Application protocolChecking…
HTTPSChecking…
Connection measurements
Run the check to see the measured values.
This is the protocol used for this page load. A different protocol on a later load is normal; this test does not measure speed.
How it works Guidance & troubleshooting
Browser and server observations
HTTP/2 carries multiple requests over a TCP connection. HTTP/3 uses QUIC over UDP, which changes how connections handle transport and packet loss. This test reports the protocol used to load this page; it does not test an arbitrary website.
Your browser’s connection and this server’s connection may use different protocols when a CDN or reverse proxy sits between them. Reload after a network or VPN change to compare a new page load, and use the TLS & HTTP signature tool for the secure connection details available to the application.
Application protocol
The application sees the final connection in the hosting path. A proxy may use a different protocol when forwarding traffic.
HTTP/3 not observed
UDP reachability, server advertisements and cached connections can affect negotiation. Another protocol does not prove HTTP/3 is unsupported.
Check after a change
Reload the page after changing your network, VPN or browser settings to create a new navigation observation.
Common questions
Does HTTP/3 always load pages faster?
No. Its benefits depend on latency, packet loss, implementation and the page itself. This tool reports protocol negotiation, not performance.
Why do the two protocol values differ?
A CDN or reverse proxy can use one protocol with your browser and another with the application.
Why can the protocol stay the same after reloading?
A browser may reuse a working connection after reloading. Seeing the same protocol is normal; this check shows the latest page load.
Why is the browser protocol unavailable?
Browser policy or privacy controls can omit Navigation Timing details. The application observation may still be available.
