Free WHOIS & DNS Lookup API — Build Domain Tools Without Scraping

Building a domain lookup tool? A competitor analysis dashboard? A phishing detection system? You need WHOIS and DNS data, but: WHOIS servers rate-limit aggressively Parsing WHOIS text responses is a nightmare (every TLD has different formats) Most WHOIS APIs charge $50+/month I built a free API that returns structured JSON for WHOIS lookups, DNS records, and domain availability — all via Cloudflare's DoH (DNS over HTTPS) for reliability. Endpoints Endpoint Method Description /whois?domain= GET WHOIS/RDAP lookup with structured JSON output /dns?domain=&type= GET DNS records (A, AAAA, MX, TXT, NS, CNAME, SOA) /available?domain= GET Domain availability check /bulk POST Bulk lookup (up to 10 domains) Quick Example — Domain Investigation Python import requests headers = { " X-RapidAPI-Key " : " YOUR_KEY " , " X-RapidAPI-Host " : " whois-domain-api.p.rapidapi.com " } whois = requests . get ( " https://whois-domain-api.p.rapidapi.com/whois?domain=example.com " , headers = headers ). json () p