SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
si-so.co.kr
SSL/TLS Certificate
SSL/TLS Certificate for si-so.co.kr
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- si-so.co.kr
- Valid from
- Oct 3, 2026
- Valid until
- Jan 1, 2027 (87 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 064DD06F120475378BE46F9924C1DC9F2D2E
- SHA-256 fingerprint
- 2E:09:BC:37:4E:81:4F:66:E6:BF:AB:7C:96:FE:0C:5B:FF:8D:40:FA:2E:51:D5:A5:EA:0C:33:55:E4:E8:4B:EB
- 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 6, 2026.
Never get surprised by si-so.co.kr's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch si-so.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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