SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
zdb-katalog.de
SSL/TLS Certificate
SSL/TLS Certificate for zdb-katalog.de
Valid- Issued by (CA)
- Hellenic Academic and Research Institutions CA
- Subject
- zdb-katalog.de
- Valid from
- Jul 22, 2026
- Valid until
- Feb 6, 2027 (125 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 0AB324B1FDF0638C94BE19158A8236CE
- SHA-256 fingerprint
- B9:21:49:53:4C:38:27:76:60:F5:C9:4B:DC:23:B5:B9:D0:19:E8:41:B1:B6:6D:70:F6:41:5A:44:0D:E1:1F:64
- Chain
- GEANT TLS RSA 1 → HARICA TLS RSA Root CA 2021
Certificate Authority Authorization (CAA)
CAA restricts issuance to harica.gr, letsencrypt.org, pki.dfn.de, sectigo.com; we couldn't map the serving CA (Hellenic Academic and Research Institutions CA) to one of these identifiers.
Never get surprised by zdb-katalog.de's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch zdb-katalog.de continuously, notifying you the moment anything moves across all three signals:
Uptime
We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.
DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
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