Question 1

Which TLS versions does my server support?

Accepted Answer

Enter your domain into the free TLS Version Checker. It opens real TLS handshakes with your server — the same way a browser does — and reports the negotiated TLS version plus the cipher, so you can confirm TLS 1.3/1.2 support and spot deprecated versions.

Question 2

How does the TLS version checker work?

Accepted Answer

It opens real TLS handshakes directly with the server, the same way a browser does, and reads the negotiated protocol and cipher from the connection. No guessing from headers: this is what the server actually negotiates.

Question 3

What TLS version should a site support?

Accepted Answer

TLS 1.3 is the modern standard and TLS 1.2 is the minimum acceptable today. TLS 1.0 and 1.1 are deprecated and considered insecure; they should be disabled.

Question 4

Why does the negotiated version matter?

Accepted Answer

The negotiated version determines the security of the encrypted connection. Old versions have known weaknesses that attackers can exploit to decrypt traffic or downgrade connections.

Question 5

Can it test every supported version, not just the negotiated one?

Accepted Answer

It reports the version negotiated by the handshake plus the cipher. Probing every legacy version individually would require many connections; the negotiated result plus cipher strength is the practical security signal.

Question 6

Does it work through CDNs?

Accepted Answer

Yes, and that is the point: it tests the TLS endpoint the public internet reaches, which is the CDN edge when one is in front. That is the connection your visitors actually get.

TLS Version Checker

Use TLS Version Checker

How to use the TLS Version Checker

Enter domain

Run the handshake

See the version

About the TLS Version Checker

Where it helps most

Confirming the fix worked

Migration verification

Hardening passes

Compliance checklists

Reading the report

1.0 and 1.1 must go

1.3 means faster too

Disabling is one line