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 sai-co.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
www.sai-co.jp
Valid from
Jul 27, 2026
Valid until
Oct 25, 2026 (73 days remaining)
Public key
RSA 2048-bit
Serial
05A64192DFBF2DBA1A682995B00F9A4F7905
SHA-256 fingerprint
0A:2D:A2:2B:34:49:23:31:38:57:42:8D:FA:70:08:77:45:74:59:2A:71:DF:38:32:BD:2A:E5:62:CF:34:CA:42
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
sai-co.jp, www.sai-co.jp

Certificate Authority Authorization (CAA)

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

This certificate has been served since Aug 6, 2026.

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Uptime

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DNS changes

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TLS certificate

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