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 katata-kango.ac.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
katata-kango.ac.jp
Valid from
Jun 25, 2026
Valid until
Sep 23, 2026 (54 days remaining)
Public key
RSA 2048-bit
Serial
05C2E2ECE7A96AB66B7C5E30A528EFBEE2BC
SHA-256 fingerprint
70:09:F5:D8:03:40:D8:6C:32:68:0C:A8:37:78:3D:1D:95:CC:CD:3E:5C:6B:7A:D4:5F:A1:79:B6:7C:01:3B:19
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (3)
katata-kango.ac.jp, webmail.katata-kango.ac.jp, www.katata-kango.ac.jp

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

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