SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
yamagata-ai.org
SSL/TLS Certificate
SSL/TLS Certificate for yamagata-ai.org
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- www.yamagata-ai.org
- Valid from
- Sep 20, 2026
- Valid until
- Dec 19, 2026 (47 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 06547EEA53ECEB31FCE0BC9F25AF4FE0870E
- SHA-256 fingerprint
- 28:EC:54:70:A3:37:65:DD:CC:C8:C4:8C:32:BA:B8:BC:7A:16:0A:AD:9F:45:56:E7:E6:F2:80:0F:44:57:F0:68
- 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.
We've observed 1 previous certificate for this host. This certificate has been served since Sep 24, 2026.
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Uptime
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DNS changes
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TLS certificate
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