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 koten-kai.jp

Expiring soon
Issued by (CA)
Let's Encrypt
Subject
koten-kai.jp
Valid from
Jun 9, 2026
Valid until
Sep 7, 2026 (20 days remaining)
Public key
EC 256-bit
Serial
05967B0D0882EC597E9C75056C3E0A3BC1E9
SHA-256 fingerprint
06:2A:60:99:2E:99:5E:6E:B3:25:30:9C:94:25:16:81:9D:49:EC:48:74:48:0B:D4:AD:EB:FC:59:BC:DC:83:99
Chain
YE2 → Root YE → ISRG Root X2 → ISRG Root X1
Subject Alternative Names (2)
koten-kai.jp, www.koten-kai.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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