SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
a-city.de
SSL/TLS Certificate
SSL/TLS Certificate for a-city.de
Hostname mismatch- Issued by (CA)
- Asseco Data Systems S.A.
- Subject
- *.m-net.de
- Valid from
- May 11, 2026
- Valid until
- Nov 26, 2026 (82 days remaining)
- Public key
- RSA 3072-bit
- Serial
- 04F711BD9FE366233516A05EB26433AB
- SHA-256 fingerprint
- 33:BF:64:72:23:A5:B8:99:88:7E:8F:47:EA:D6:5E:0E:44:D0:A4:AF:DB:13:0D:3C:40:0A:CD:F3:17:10:BE:9D
- Chain
- Certum DV TLS G2 R39 CA → Certum Trusted Root CA → Certum Trusted Network CA
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 31, 2026.
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Uptime
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DNS changes
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TLS certificate
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