SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
bj21.builders
SSL/TLS Certificate
SSL/TLS Certificate for bj21.builders
No TLS certificate could be retrieved (getaddrinfo ENOTFOUND bj21.builders).
The domain may not serve HTTPS, may be unreachable, or may not present a certificate on port 443. You can still review its DNS records.
Never get surprised by bj21.builders's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch bj21.builders 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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