SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
SSL/TLS Certificate for 20-21.de
Hostname mismatch- Issued by (CA)
- Asseco Data Systems S.A.
- Subject
- 20-21.art
- Valid from
- Feb 19, 2026
- Valid until
- Feb 19, 2027 (162 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 3F6F0CB832C6C2A29A99B183C97610
- SHA-256 fingerprint
- 7F:40:98:69:5D:AC:10:0B:C9:2C:BE:20:18:4D:12:D0:5E:5D:3C:A6:B7:E8:69:79:8B:3F:CC:7D:FF:22:7D:14
- Chain
- Certum DV TLS G2 R39 CA → Certum Trusted Root CA
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
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DNS changes
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TLS certificate
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