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 tk-01.jp
Valid- Issued by (CA)
- GlobalSign nv-sa
- Subject
- www.tk-01.jp
- Valid from
- Mar 18, 2026
- Valid until
- Oct 3, 2026 (22 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 7580EFC017DF0C5943648E91
- SHA-256 fingerprint
- 8C:C9:11:87:86:6A:0B:64:A9:0F:B8:87:97:AE:8C:ED:BD:6A:AD:03:7D:37:D6:A6:C3:D1:EF:15:65:6A:75:5D
- Chain
- GlobalSign GCC R6 AlphaSSL CA 2025 → GlobalSign → GlobalSign
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 Sep 4, 2026.
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Uptime
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DNS changes
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TLS certificate
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