Expired certificates still take down big sites every year. If you run an agency, a hosting panel or an uptime tool, you want cert expiry, DNS and a quick security check for every client domain, without running openssl in cron jobs.

SSL check 

curl "https://domainkit-dns-ssl-whois-website-tech-lookup.p.rapidapi.com/ssl?domain=github.com" \ -H "X-RapidAPI-Key: $KEY" \ -H "X-RapidAPI-Host: domainkit-dns-ssl-whois-website-tech-lookup.p.rapidapi.com" 
{"domain": "github.com", "valid": true, "days_remaining": 46, "issuer": {"organizationName": "Sectigo Limited"}, "protocol": "TLSv1.3", "san": ["github.com", "www.github.com"]}

Alert when days_remaining < 14 and you're done.

Website scan

/scan?domain=stripe.com returns the server, the detected technologies (Next.js, nginx), the redirect chain, and a security score based on HSTS, CSP, X-Frame-Options and similar headers. That's useful for sales prospecting ("your site is missing HSTS") and for client audits.

Also included

  • /dns: A, AAAA, MX, TXT, NS, CNAME and SPF/DMARC in one call
  • /whois: registrar, creation date and expiry (RDAP)

Free tier: 200 calls/month. DomainKit on RapidAPI