SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
r-data.com.tw
SSL/TLS Certificate
SSL/TLS Certificate for r-data.com.tw
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- www.r-data.com.tw
- Valid from
- Jun 5, 2026
- Valid until
- Sep 3, 2026 (30 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 05BA03A1002B01124C76AB468FA6FB6FB3D7
- SHA-256 fingerprint
- A6:4F:51:6A:DC:58:2D:A0:DD:8C:6C:5C:4C:4C:F8:2D:43:64:9B:7A:CE:5B:C5:93:78:C3:41:FD:BF:8E:D0:2C
- 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.
Never get surprised by r-data.com.tw's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch r-data.com.tw 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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