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SSL Certificate Checker

Peek TLS certificate metadata with SSRF-safe hostname rules

About SSL Certificate Checker

SSL Certificate Checker opens a short-lived TLS handshake from UtilityKit to your chosen public hostname so you can audit issuer names, validity windows, subject alternative names, and fingerprints without piping openssl through your laptop. It complements the HTTP headers utility when diagnosing mixed-content warnings or sudden hostname mismatches.

Why use SSL Certificate Checker

  • Spot imminent expiry without SSH access to servers.
  • Verify SAN coverage before flipping DNS.
  • Share structured output that complements browser padlock icons.

How to use SSL Certificate Checker

  1. Enter the hostname (no scheme).
  2. Adjust the port if you terminate TLS on a non-standard listener.
  3. Inspect JSON describing issuer, dates, and fingerprints.

When to use SSL Certificate Checker

  • Renewal dress rehearsals before ACME jobs fail silently.
  • Customer success confirming SAN lists after migrations.
  • Security reviews documenting cert lineage.

Frequently Asked Questions

Does this validate trust chains?

Verification is relaxed so expired or mis-issued certs remain visible for debugging.

Can I scan internal hosts?

No — the same SSRF protections apply as other network utilities.

Which fingerprints appear?

SHA-256 (and related metadata returned by the TLS inspector service).

Does it replace Certificate Transparency monitoring?

No — use it for spot checks, not continuous telemetry.

Is SSL Certificate Checker free?

Yes — open the tool without signing up.

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