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 kotsu-daigaku.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
kotsu-daigaku.jp
Valid from
Jun 19, 2026
Valid until
Sep 17, 2026 (56 days remaining)
Public key
RSA 4096-bit
Serial
05C5011CA2BA131691EA66286220CE1B2136
SHA-256 fingerprint
AA:05:65:81:9B:DA:62:94:A0:BC:2A:DC:BB:B9:5F:5B:2F:6C:B1:7E:AD:C4:49:02:35:76:F7:55:EF:18:55:B7
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
kotsu-daigaku.jp, www.kotsu-daigaku.jp

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 22, 2026.

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TLS certificate

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