SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
opensym.org
SSL/TLS Certificate
SSL/TLS Certificate for opensym.org
Valid- Issued by (CA)
- Hellenic Academic and Research Institutions CA
- Subject
- www.opensym.org
- Valid from
- Jan 20, 2026
- Valid until
- Jan 20, 2027 (120 days remaining)
- Public key
- EC 384-bit
- Serial
- 0BF498EC20F4A043EA2A781232140CC7
- SHA-256 fingerprint
- A9:F0:0D:59:88:35:96:CC:5C:15:B6:7A:04:4B:B4:9A:5F:F6:F5:B3:18:B4:37:6C:BD:0C:2F:51:7A:84:D5:DD
- Chain
- GEANT TLS ECC 1 → HARICA TLS ECC Root CA 2021 → Hellenic Academic and Research Institutions ECC RootCA 2015
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 2, 2026.
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DNS changes
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TLS certificate
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