SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
k-yu-sei.co.jp
SSL/TLS Certificate
SSL/TLS Certificate for k-yu-sei.co.jp
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- k-yu-sei.co.jp
- Valid from
- Sep 30, 2026
- Valid until
- Dec 29, 2026 (53 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 05E7FDEF6B40177A65ED733E12605047A2C8
- SHA-256 fingerprint
- F6:05:B6:97:F6:75:2A:4A:E4:24:9F:AE:26:76:A2:F4:BA:70:1D:94:F4:99:01:BC:18:B4:C0:D6:FD:60:94:73
- 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 22, 2026.
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Uptime
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DNS changes
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TLS certificate
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