SSLWatchTLS 1.2 vs TLS 1.3: what is the difference?
TLS 1.3 is faster and safer than TLS 1.2. Here is what changed and how to check which one a site uses.
TLS 1.3 (2018) cuts the handshake to one round trip, removes old ciphers like RSA key exchange and CBC modes, and always uses forward secrecy.
TLS 1.2 is still acceptable when configured with modern ciphers. TLS 1.0 and 1.1 are deprecated and blocked by all major browsers.
Our checker shows the negotiated TLS version for any domain.