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 oimachi-keio.com

Valid
Issued by (CA)
Let's Encrypt
Subject
oimachi-keio.com
Valid from
Jun 4, 2026
Valid until
Sep 2, 2026 (41 days remaining)
Public key
RSA 2048-bit
Serial
05C598DDD1DED5418F58B55D3506042AB72F
SHA-256 fingerprint
28:A0:88:16:04:62:02:97:55:73:33:63:32:55:98:42:75:F5:1F:C0:8E:D8:C6:3B:4B:12:58:E4:45:E0:E1:FE
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (1)
oimachi-keio.com

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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