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 sio.si
Valid- Issued by (CA)
- Hellenic Academic and Research Institutions CA
- Subject
- sio.si
- Valid from
- Aug 17, 2026
- Valid until
- Mar 4, 2027 (163 days remaining)
- Public key
- EC 256-bit
- Serial
- 76F0CBEA25D1351A70A924D6FD49BD12
- SHA-256 fingerprint
- A7:98:BC:82:36:95:70:EE:9B:95:67:48:93:BE:65:75:B5:45:87:D9:22:29:A9:62:E2:48:03:A1:2C:00:FC:A7
- 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.
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Uptime
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DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
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