The server presented this certificate. Here's what's in it — expiry, chain, issuer, and covered hostnames.
Certline connects to a server over TLS, reads the certificate it actually presents, and reports what it found — the date, the issuer, every hostname the certificate covers, and whether the chain is complete. The tool is a conduit, not a judge: what the server said is what you see.
What the report contains
- Expiry date & days remaining
- When the certificate becomes invalid, and how many days are left. Expired and not-yet-valid certificates are flagged with a clear status badge.
- Issuer
- Who issued the certificate — the Certificate Authority that signed it, extracted from the issuer field.
- Subject Alternative Names (SANs)
- Every hostname the certificate covers. This is how you check whether a certificate was issued for the server you’re actually connecting to.
- Certificate chain & completeness
- Whether the server sent its intermediate certificate. A certificate can be valid and the site still break because the server omitted the intermediate — desktop browsers paper over it from cache, but mobile clients do not. This tool reports exactly what the server sent.
- Fingerprint & key details
- The SHA-256 fingerprint, serial number, and key bit length — raw data from the certificate for verification against known values.
This tool runs one check at a time. It does not send alerts, track history, or scan subdomains. It reports what the server presented — nothing more, nothing inferred.