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 sa-i.kr
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- sa-i.kr
- Valid from
- Oct 8, 2026
- Valid until
- Jan 6, 2027 (66 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 052667659CFA4330841FF5D64019E2CFF620
- SHA-256 fingerprint
- A0:11:12:E8:D9:BB:1A:83:DA:2D:6C:06:33:D8:CC:36:54:C8:C9:9E:A8:89:1B:BC:A4:7A:98:B8:97:F2:5F:F7
- Chain
- YR1 → Root YR → ISRG Root X1
Certificate Authority Authorization (CAA)
The serving CA (Let's Encrypt) is authorized by this domain's CAA records (letsencrypt.org, pki.goog, sectigo.com).
We've observed 2 previous certificates for this host. This certificate has been served since Oct 18, 2026.
Never get surprised by sa-i.kr's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch sa-i.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, CNAME, TXT 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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