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 czu.cz
Valid- Issued by (CA)
- Hellenic Academic and Research Institutions CA
- Subject
- *.czu.cz
- Valid from
- Sep 18, 2026
- Valid until
- Apr 5, 2027 (154 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 59AA5CC11491735BD290AEE7322DC9DF
- SHA-256 fingerprint
- 00:E0:AD:3A:19:66:F6:ED:78:E9:46:97:08:7C:40:2B:57:B2:69:3C:CC:5D:A7:FF:E4:0E:62:C7:B8:D6:29:85
- Chain
- GEANT TLS RSA 1 → HARICA TLS RSA Root CA 2021 → Hellenic Academic and Research Institutions RootCA 2015
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
We've observed 1 previous certificate for this host. This certificate has been served since Sep 20, 2026.
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Uptime
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DNS changes
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TLS certificate
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