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 rug.nl
Valid- Issued by (CA)
- Hellenic Academic and Research Institutions CA
- Subject
- www.rug.nl
- Valid from
- Dec 1, 2025
- Valid until
- Dec 1, 2026 (128 days remaining)
- Public key
- EC 256-bit
- Serial
- 0B1A4F673323A8279F8432580247854B
- SHA-256 fingerprint
- B4:E3:BE:6E:16:94:A2:20:31:2D:23:4F:E2:87:28:43:46:19:C5:E0:30:92:A4:BC:CD:31:AE:C8:8E:B5:30:E6
- 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 Jul 21, 2026.
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DNS changes
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TLS certificate
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