SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
a-matter.de
SSL/TLS Certificate
SSL/TLS Certificate for a-matter.de
Self-signed- Issued by (CA)
- empty
- Subject
- localhost
- Valid from
- Jun 9, 2026
- Valid until
- Jun 8, 2028 (637 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 618FE31820AA13E6
- SHA-256 fingerprint
- E9:3B:35:3F:3B:3D:FA:5F:C4:E3:E6:0C:F7:B9:F8:F2:32:A9:68:95:8A:69:FD:BC:C2:E6:73:D4:E8:6A:7E:12
- Chain
- localhost
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 Sep 5, 2026.
Never get surprised by a-matter.de's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch a-matter.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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