SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
ot-sec.de
SSL/TLS Certificate
SSL/TLS Certificate for ot-sec.de
Valid- Issued by (CA)
- Sectigo Limited
- Subject
- ot-sec.de
- Valid from
- Oct 10, 2025
- Valid until
- Oct 24, 2026 (86 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 1723ECA08321A7F18530029AD3C76A26
- SHA-256 fingerprint
- C8:F1:F6:C6:52:AF:72:66:FB:88:A8:47:EC:F5:24:8E:D1:47:FE:4F:B4:6E:07:47:29:97:FB:7E:51:58:F9:75
- Chain
- Sectigo Public Server Authentication CA DV R36 → Sectigo Public Server Authentication Root R46 → USERTrust RSA Certification Authority
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
Never get surprised by ot-sec.de's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch ot-sec.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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