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-ter.fr
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- a-ter.fr
- Valid from
- Aug 13, 2026
- Valid until
- Nov 11, 2026 (37 days remaining)
- Public key
- EC 256-bit
- Serial
- 06611CA6C2A8C7FDC21C14E78B0ACC82A49C
- SHA-256 fingerprint
- 93:DA:BA:56:A5:33:C5:37:83:93:14:0A:3D:A9:85:A3:E7:66:83:05:FC:00:BF:60:46:94:14:44:BE:F8:6A:0E
- Chain
- YE1 → Root YE → ISRG Root X2 → ISRG Root X1
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 23, 2026.
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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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