SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
act-s.co.kr
SSL/TLS Certificate
SSL/TLS Certificate for act-s.co.kr
Hostname mismatch- Issued by (CA)
- Let's Encrypt
- Subject
- wp01.nayana.kr
- Valid from
- Oct 6, 2026
- Valid until
- Jan 4, 2027 (87 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 064A289CD8979148485AF6613DD9FDFDB755
- SHA-256 fingerprint
- A8:13:6E:25:5F:24:E4:74:42:88:D3:8C:38:82:79:E6:02:59:3D:51:D7:97:08:2E:96:8C:BA:FF:2A:D3:3A:6C
- 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 3, 2026.
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Uptime
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DNS changes
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TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
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