SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
dr-seitner.com
SSL/TLS Certificate
SSL/TLS Certificate for dr-seitner.com
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- dr-seitner.com
- Valid from
- Sep 20, 2026
- Valid until
- Dec 19, 2026 (81 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 061E468781FA13187CD27134AD573B63CA4C
- SHA-256 fingerprint
- FE:50:94:91:4D:3A:06:83:FB:F4:E3:4D:C5:CF:77:50:05:2F:B9:C4:09:31:3B:2E:6D:C5:6B:23:18:28:7F:AB
- Chain
- YR2 → Root YR → ISRG Root X1
Certificate Authority Authorization (CAA)
The serving CA (Let's Encrypt) is authorized by this domain's CAA records (letsencrypt.org).
We've observed 1 previous certificate for this host. This certificate has been served since Sep 25, 2026.
Never get surprised by dr-seitner.com's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch dr-seitner.com 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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