SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
kosei-kai.or.jp
SSL/TLS Certificate
SSL/TLS Certificate for kosei-kai.or.jp
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- www.kosei-kai.or.jp
- Valid from
- Oct 9, 2026
- Valid until
- Jan 7, 2027 (61 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 050BFD5893F6B6B9488AB32E95E6CB7956E1
- SHA-256 fingerprint
- 2E:1F:40:D8:67:36:7A:CC:9B:96:FD:D4:27:62:DF:9C:A8:A9:2C:CC:39:23:E8:29:F2:E4:2D:F4:9E:8B:2E:14
- Chain
- YR1 → Root YR → ISRG Root X1
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 28, 2026.
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Uptime
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DNS changes
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TLS certificate
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