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 a-z.lu
Valid- Issued by (CA)
- Hellenic Academic and Research Institutions CA
- Subject
- *.a-z.lu
- Valid from
- Oct 15, 2025
- Valid until
- Oct 15, 2026 (82 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 6D5EB68772175E1DC85A4A8A2A45F2BA
- SHA-256 fingerprint
- CA:D0:C5:50:76:14:0B:E7:7D:AC:43:E9:0F:9C:71:D7:DA:CD:03:70:78:AE:30:44:3F:1E:A2:7A:9E:07:C5:85
- 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.
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Uptime
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DNS changes
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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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