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 k-flag.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
k-flag.jp
Valid from
Jul 9, 2026
Valid until
Oct 7, 2026 (75 days remaining)
Public key
RSA 2048-bit
Serial
055F27E4E56ED111FA9A41356C7D8CC3AEB4
SHA-256 fingerprint
98:74:2F:1E:7F:FB:84:43:61:2F:DC:13:A4:C1:1C:68:65:32:3F:5F:BE:94:14:55:F2:B4:15:88:D2:B3:C7:3C
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
*.k-flag.jp, k-flag.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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