Browser protocol
Navigation Timing reports the protocol used for this page, usually h2 for HTTP/2 or h3 for HTTP/3. Checking again does not reload the page.
Free network tool
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…
This is the protocol used for this page load. A different protocol on a later load is normal; this test does not measure speed.
Two views of the same request
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 and the application may see 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 fingerprint test 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.
View HTTP and TLS details
Run the test to see its detected details.
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 does “Check again” show the same browser protocol?
The browser value belongs to the current page navigation. Reload the page to inspect a new navigation.
Why is the browser protocol unavailable?
Browser policy or privacy controls can omit Navigation Timing details. The application observation may still be available.
