TLS Checker
Check TLS versions and cipher support for any domain. Confirm you're on TLS 1.2 and 1.3 and free of deprecated ciphers.
About TLS Checker
Modern browsers, PCI DSS and every major compliance framework require TLS 1.2 or 1.3 with strong ciphers. Anything older exposes users to downgrade and cipher-suite attacks that undermine your entire security story. This tool negotiates against your server and reports exactly which protocols and cipher families are enabled.
What this tool checks
TLS Checker focuses on the following signals from your site's live response:
tlsmodule in the full auditsslmodule in the full audit
Why it matters
Signals covered by TLS Checker are the ones attackers, browsers, and search engines look at first. A weak result here means real users are exposed — via downgrade attacks, broken trust warnings, indexing problems, or leaked data — long before anything obvious breaks. Fixing them is usually a config change, not a rewrite, and the impact is immediate.
How to interpret your result
- Pass — the signal meets modern best practice. Keep it monitored; regressions happen after deploys.
- Warn — functional but weaker than recommended. Usually a quick header, DNS, or config tweak away from a full pass.
- Fail — a real risk to users or search visibility. Follow the recommendation shown next to the finding — it's copy-pasteable.
Best practices
- • Re-run after every deploy — configuration drift is the #1 cause of regressions.
- • Compare against a competitor's report to spot easy wins.
- • Wire the public API into CI to gate merges on the score.
- • Fix warns before failures — they're the cheapest to close and pay off compounding gains.
Frequently asked questions
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