SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
k-kousya.or.jp
SSL/TLS Certificate
SSL/TLS Certificate for k-kousya.or.jp
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- k-kousya.or.jp
- Valid from
- Aug 5, 2026
- Valid until
- Nov 3, 2026 (78 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 05AA045851A0ADA7FBFC11F6B28C171D4118
- SHA-256 fingerprint
- 93:E9:32:9D:80:AE:7D:AC:BD:46:49:06:DA:27:58:04:66:62:B1:A6:D2:7F:1A:B2:77:C3:D4:B1:71:9E:4C:87
- Chain
- YR2 → Root YR → ISRG Root X1
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
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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