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 nagao.or.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
nagao.or.jp
Valid from
Jul 26, 2026
Valid until
Oct 24, 2026 (67 days remaining)
Public key
RSA 2048-bit
Serial
052DB5A14D0A9DC76B62870890216A15974E
SHA-256 fingerprint
D2:EE:F1:DD:C6:6A:D9:D9:30:77:C9:20:CD:C2:CF:B5:1F:4A:CF:55:F5:40:E3:C1:2F:7C:3F:5E:FE:59:A2:06
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
nagao.or.jp, www.nagao.or.jp

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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