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 simsdl.fr

Valid
Issued by (CA)
Let's Encrypt
Subject
simsdl.fr
Valid from
Aug 14, 2026
Valid until
Nov 12, 2026 (75 days remaining)
Public key
RSA 2048-bit
Serial
06420D48A20704C74909AC7ED2C6360E69AF
SHA-256 fingerprint
91:2C:CD:1D:72:02:E4:DD:F2:02:5C:30:03:DB:7A:B1:BF:56:85:60:18:82:75:3A:ED:90:A1:D0:A6:E3:A2:06
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (4)
mail.simsdl.fr, simsdl.fr, webmail.simsdl.fr, www.simsdl.fr

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 Aug 9, 2026.

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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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