Load ipthing.net over HTTPS to see the handshake this server negotiated with your client: TLS version, cipher suite, ALPN, key exchange, and JA3/JA4 fingerprints from the ClientHello.
h2 or h3)Plain HTTP has no TLS rows. curl over HTTPS includes the same fields in JSON.
JA3 (older) and JA4 (current) summarise how a TLS library builds its ClientHello. Browsers that share a stack share a hash; so do many copies of curl. They are useful to tell “browser-like” from “script-like” traffic. They do not identify a person. Aggregate JA3/JA4 frequencies are on stats.ipthing.net without joining hashes back to individual IPs.
HTTPS serves HTTP/1.1 and HTTP/2 on TCP 443. HTTP/3 (QUIC) listens on UDP 443 and is advertised with Alt-Svc. If UDP/443 is blocked on the path, you will still get HTTP/2. The Protocol field on the live page is what was actually used.
Related: request headers your client sent alongside the handshake.