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 osako-seikei.com

Valid
Issued by (CA)
Let's Encrypt
Subject
osako-seikei.com
Valid from
Jul 1, 2026
Valid until
Sep 29, 2026 (57 days remaining)
Public key
RSA 2048-bit
Serial
05FA7206EFF10D34B643B7AE628E57F46ACD
SHA-256 fingerprint
68:50:C2:2F:1A:A0:62:D5:6E:13:BA:58:E5:7D:26:A3:AC:8F:5C:36:DA:23:E0:B4:C4:3F:DF:5C:0E:CE:4E:39
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
osako-seikei.com, www.osako-seikei.com

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 2, 2026.

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Uptime

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DNS changes

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TLS certificate

We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.

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