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 kanmon-const.co.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
www.kanmon-const.co.jp
Valid from
Sep 23, 2026
Valid until
Dec 22, 2026 (86 days remaining)
Public key
RSA 2048-bit
Serial
05829F800B16C3A11441C1458580D94A4220
SHA-256 fingerprint
4D:98:FC:B3:5B:FC:C2:D9:E0:36:62:D7:61:AF:4E:25:C2:9A:32:C1:8A:75:12:11:81:FA:69:74:80:BC:17:D1
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
kanmon-const.co.jp, www.kanmon-const.co.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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