{
  "id": 471755,
  "title": "I Compared 12 WHOIS APIs — Subdomain Center Won on 3 Metrics",
  "url": "https://urgent.news/2026/08/10/i-compared-12-whois-apis-subdomain-center-won-on-3-metrics",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-08-10T13:37:58.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/onizuka/i-compared-12-whois-apis-subdomain-center-won-on-3-metrics-2nll"
  },
  "original_language": "en",
  "account": "I conducted an experiment comparing 12 different WHOIS APIs, focusing on subdomain discovery capabilities. The results were strikingly varied. The subdomain.center API emerged as the clear standout, returning a massive 11,847 subdomains for the target domain stripe.com, coupled with full DNS records, SSL metadata, takeover-risk scores, and an email-security report—all within a remarkably low cost of roughly $0.002 per call.\n\nIn contrast, the worst-performing API, also Stripe's Subdomain Center, returned an astonishing 312 subdomains for the same domain but charged $0.09 per call. This significant discrepancy in performance and cost highlighted a wide range of capabilities among the APIs tested. Most of these WHOIS APIs primarily serve as domain-age lookup services, providing basic information such as registration dates but falling short in delivering critical detailed data like subdomain enumeration, DNS record analysis, and security assessments.\n\nThe limitations of these APIs became evident when attempting to perform comprehensive bug bounty recon. Many of these services merely offered superficial domain registration details, missing out on crucial indicators like dangling subdomains (e.g., docs.example.com on GitHub Pages) or missing security records (e.g., missing mta-sts.example.com). Furthermore, these APIs often failed to detect changes in security configurations, such as SPF record updates, which could indicate vulnerabilities.\n\nThis led to the necessity of chaining multiple APIs, including amass, subfinder, dnsx, and others, into a complex pipeline. Such a setup was not only cumbersome but also prone to breaking whenever any single vendor altered a field or imposed new rate limits. The entire process was slow, demanding substantial computational resources, and often became impractical to execute on low-power devices like smartphones.\n\nTo address these issues, I developed a small harness that systematically called each API, measured response times, counted subdomains, assessed DNS record coverage, and scored the inclusion of key security fields like takeover-risk and email-security. The results clearly demonstrated the superior performance and cost-effectiveness of the Subdomain Center API, making it the optimal choice for efficient and thorough subdomain reconnaissance.",
  "summary": "cybersecurity, #api, #python, #sideprojects The benchmark that embarrassed my wallet I burned $47 in API credits in 14 minutes. Same domain. Twelve different WHOIS endpoints. The worst one returned 312 subdomains and charged $0.09 per call. The best one returned 11,847 subdomains, full DNS records, SSL metadata, takeover-risk scores, and an email-security report, all for roughly $0.002 per call.…",
  "key_points": [
    "Subdomain.center API returned 11,847 subdomains for stripe.com",
    "Worst-performing API returned only 312 subdomains for same domain",
    "Subdomain Center API is cost-effective at $0.002 per call"
  ],
  "editors_take": "The Subdomain Center API's standout performance and low cost signify a shift in favor of specialized services over general WHOIS APIs for comprehensive subdomain discovery and security assessments.",
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}