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 o-s.de
Valid- Issued by (CA)
- Deutsche Telekom Security GmbH
- Subject
- *.operational-services.de
- Valid from
- Feb 23, 2026
- Valid until
- Feb 27, 2027 (166 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 3258196AA460DB3EAC90DB25582849B7
- SHA-256 fingerprint
- 2E:08:C7:43:2E:DE:76:66:CA:B6:00:8D:22:42:81:86:AC:82:64:45:2C:D5:A9:2C:48:1C:FA:C8:D2:E1:63:33
- Chain
- Telekom Security ServerID OV Class 2 CA → T-TeleSec GlobalRoot Class 2
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
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TLS certificate
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