SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
ruhr-uni-bochum.de
SSL/TLS Certificate
SSL/TLS Certificate for ruhr-uni-bochum.de
Valid- Issued by (CA)
- Hellenic Academic and Research Institutions CA
- Subject
- san4.ruhr-uni-bochum.de
- Valid from
- Feb 19, 2026
- Valid until
- Feb 19, 2027 (110 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 1DDF289ED75B82A283113FE6099FECF3
- SHA-256 fingerprint
- 2B:8A:BA:DD:2A:A7:2C:0A:80:66:9D:A5:06:73:80:0E:86:30:C9:CA:AB:E8:B8:4E:4B:33:E4:3F:BA:1C:77:05
- Chain
- GEANT TLS RSA 1 → HARICA TLS RSA Root CA 2021 → Hellenic Academic and Research Institutions RootCA 2015
Certificate Authority Authorization (CAA)
CAA restricts issuance to harica.gr, letsencrypt.org, pki.dfn.de, sectigo.com, telesec.de, zerossl.com; we couldn't map the serving CA (Hellenic Academic and Research Institutions CA) to one of these identifiers.
This certificate has been served since Aug 2, 2026.
Never get surprised by ruhr-uni-bochum.de's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch ruhr-uni-bochum.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, CNAME, TXT 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.
Free for your first domain: uptime, DNS, and certificate together. No credit card.