HTTP3 IP-Checker - Test IP Addresses for HTTP3 Support
Test specific IP addresses and custom ports for HTTP3 and QUIC protocol support
example.com
QUIC is not supported
HTTP/3 is not supported
HTTP/3 is not supported by this endpoint. The server is currently using HTTP/2.
| Connection ID | Packet RX | Handshake Done |
|---|---|---|
| 6e64d0e4... | 4.89 | 2.46 |
Server Information
Response Headers
| Header | Value |
|---|---|
| date | Wed, 11 Mar 2026 05:48:12 GMT |
| content-type | text/html |
| cf-ray | 9da844d19d92cab4-FRA |
| last-modified | Thu, 05 Mar 2026 11:54:13 GMT |
| allow | GET, HEAD |
| accept-ranges | bytes |
| age | 11463 |
| cf-cache-status | HIT |
| server | cloudflare |
HTTP/3 Statistics
Connection ID
This unique identifier for a QUIC connection is used to ensure that changes to an endpoint's lower network layer address (UDP/IP) does not affect the delivery of the QUIC connection's packets.
This tool attempts two connections to test the server's 0-RTT capabilities. During the first connection, the client receives important handshake material from the server. With 0-RTT, the client can start to send data immediately if it uses this handshake material when it creates the second connection.
Packet RX
This value represents the time between the first packet sent and the first packet received (measured in milliseconds).
Handshake Done
This value represents the time between when the first packet is sent and when the handshake is completed (measured in milliseconds).
Take notice of the difference in this metric between the first connection and the second connection. Using 0-RTT, future connections (i.e. the second connection) can complete the handshake much faster than the original connection.