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 gumi-lab.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
www.gumi-lab.jp
Valid from
Sep 8, 2026
Valid until
Dec 7, 2026 (87 days remaining)
Public key
RSA 2048-bit
Serial
06E21909A29F19ECAB37168EC12A859E5BB0
SHA-256 fingerprint
5D:1B:C2:38:0F:02:62:19:28:22:85:E5:01:F1:82:10:60:94:00:FD:61:EF:32:38:CF:CB:1F:98:18:E1:B4:C0
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
gumi-lab.jp, www.gumi-lab.jp

Certificate Authority Authorization (CAA)

No CAA policy is published for this domain — any certificate authority may issue for it.

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DNS changes

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TLS certificate

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