SSL/TLS Certificate Lookup

Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted

at-act.jp

SSL/TLS Certificate

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SSL/TLS Certificate for at-act.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
cpcalendars.at-act.jp
Valid from
Sep 9, 2026
Valid until
Dec 8, 2026 (52 days remaining)
Public key
RSA 2048-bit
Serial
067372DE784B13C1D72514117BAD3456D2C1
SHA-256 fingerprint
97:2D:40:65:10:F4:11:99:25:CD:5E:11:67:45:0D:73:C7:B1:EC:00:9F:70:95:65:B2:BD:C7:C5:84:DC:EB:14
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (22)
at-act-jp.cfbx.jp, at-act.jp, autoconfig.at-act-jp.cfbx.jp, autoconfig.at-act.jp, autodiscover.at-act-jp.cfbx.jp, autodiscover.at-act.jp, cpanel.at-act-jp.cfbx.jp, cpanel.at-act.jp, cpcalendars.at-act-jp.cfbx.jp, cpcalendars.at-act.jp, cpcontacts.at-act-jp.cfbx.jp, cpcontacts.at-act.jp, mail.at-act-jp.cfbx.jp, mail.at-act.jp, pre.at-act-jp.cfbx.jp, webdisk.at-act-jp.cfbx.jp, webdisk.at-act.jp, webmail.at-act-jp.cfbx.jp, webmail.at-act.jp, www.at-act-jp.cfbx.jp, www.at-act.jp, www.pre.at-act-jp.cfbx.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 Oct 7, 2026.

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DNS changes

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TLS certificate

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