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 mseikan.com

Valid
Issued by (CA)
Let's Encrypt
Subject
hitozuma.samplelabo.jp
Valid from
Oct 27, 2026
Valid until
Jan 25, 2027 (86 days remaining)
Public key
RSA 2048-bit
Serial
06C889181C7A39FA2FFE7CA07D2042DDA33D
SHA-256 fingerprint
2B:BC:B3:82:8F:58:E7:22:B2:CF:61:40:FC:AF:CC:B9:2A:C6:1E:F9:09:03:7A:17:C7:7B:2E:0E:41:04:4B:BC
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (12)
gekiyasu.samplelabo.jp, hitozuma.samplelabo.jp, mseikan.com, mseikan.samplelabo.jp, www.gekiyasu.samplelabo.jp, www.hitozuma.samplelabo.jp, www.mseikan.com, www.mseikan.samplelabo.jp, www.xn--49sy4eryw.tokyo, www.xn--gmq11y.tokyo, xn--49sy4eryw.tokyo, xn--gmq11y.tokyo

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 Sep 24, 2026.

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TLS certificate

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