SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
sebastian-brummer.org
SSL/TLS Certificate
SSL/TLS Certificate for sebastian-brummer.org
Self-signed- Issued by (CA)
- Default SSL Certificate
- Subject
- Default SSL Certificate
- Valid from
- Apr 29, 2016
- Valid until
- Apr 29, 2019 (expired 2709 days ago)
- Public key
- RSA 2048-bit
- Serial
- 5723105F00052D06
- SHA-256 fingerprint
- 27:7D:96:A7:7E:24:06:F4:3C:40:8A:8C:AB:D2:CA:34:59:EF:60:4D:B1:60:01:39:D8:34:45:C1:2D:FC:16:D5
- Chain
- Default SSL Certificate
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
This certificate has been served since Aug 24, 2026.
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Uptime
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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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