SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
x-core.co.kr
SSL/TLS Certificate
SSL/TLS Certificate for x-core.co.kr
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- x-core.co.kr
- Valid from
- Aug 25, 2026
- Valid until
- Nov 23, 2026 (55 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 0503E06CFCE64D454F9B762807750002A8FB
- SHA-256 fingerprint
- 26:3E:2E:64:8A:23:D3:40:E8:26:D8:0A:38:75:11:0E:1A:46:B7:E3:D5:E0:C2:E5:4A:8D:17:6E:61:91:38:98
- 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 Aug 18, 2026.
Never get surprised by x-core.co.kr's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch x-core.co.kr continuously, notifying you the moment anything moves across all three signals:
Uptime
We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.
DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
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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