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 oppus.one

Valid
Issued by (CA)
Let's Encrypt
Subject
*.oppus.one
Valid from
Sep 4, 2026
Valid until
Dec 3, 2026 (82 days remaining)
Public key
RSA 2048-bit
Serial
068F66C906D7C5BF2D49BDEB0CAB813F4F8B
SHA-256 fingerprint
AD:2A:F4:6D:DC:53:87:C8:E1:FE:F5:02:49:89:0F:65:29:FE:58:85:C2:1C:B6:36:65:7D:DF:CA:58:F6:34:CB
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
*.oppus.one, oppus.one

Certificate Authority Authorization (CAA)

The serving CA (Let's Encrypt) is authorized by this domain's CAA records (letsencrypt.org, pki.goog, sectigo.com).

We've observed 1 previous certificate for this host. This certificate has been served since Sep 4, 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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