WhoisJSON API
WhoisJSON API: A focused domain-intelligence API with a free tier and plans from $10/month. Ranked #4 of 27 in WHOIS Lookup Tools by our editors (8.8/10); pricing: Free plan; best for API users needing WHOIS plus domain intelligence.
At a glance
- Editor score8.8 / 10
- PricingFree plan
- Best forAPI users needing WHOIS plus domain intelligence
- Free planYes
- Paid from$10/mo
- Facts checked20 Sep 2026
Where it wins
- Combines WHOIS, DNS, SSL, availability, and monitoring endpoints
- Adds subdomain discovery and email-domain signup risk scoring
- Supports JSON output with integrations for PHP, Python, and Node.js
Where it doesn't
- It is an API service rather than a conventional API client
- XML support is limited to qualifying plans
- Higher-volume access requires moving through multiple paid tiers
Our verdict on WhoisJSON API
WhoisJSON API is a hosted REST API for developers and businesses that need structured domain intelligence. Its endpoints cover WHOIS and RDAP registration lookups, DNS record resolution, SSL/TLS certificate validation, real-time domain availability, subdomain discovery, email-domain intelligence, and domain monitoring with change alerts. The product fits cybersecurity, hosting, fraud-prevention, brand-protection, SaaS, and domain-management workflows, especially when applications need machine-readable responses rather than a graphical lookup interface.
Pricing is organized around a free Basic plan and seven paid tiers. Basic costs $0 per month and includes the WHOIS, DNS, SSL, domain availability, email intelligence, subdomain discovery, and monitoring endpoints with JSON output. Pro is $10 per month and adds all seven API endpoints, while Ultra, Scale, and Mega cost $30, $50, and $80 per month respectively; Mega also lists unlimited requests. Giga, Tera, and Titan cost $120, $200, and $399 per month, and each lists unlimited requests with all seven API endpoints. The published plans show monthly billing, while yearly billing costs the price of 10 months.
Its main strength is breadth within domain intelligence: one API can support registration data, infrastructure records, certificate checks, availability, discovery, monitoring, and email-domain risk scoring. A single authentication token is used across the endpoints, and integrations are listed for PHP, Python, Node.js, Claude, Cursor, and Windsurf. JSON is standard, with XML support on qualifying plans. Choose WhoisJSON API when an application needs several domain-data functions behind an API and a free starting point. It is less suitable for buyers seeking a conventional API client or a standalone interface for manual lookups.
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WhoisJSON API pricing
All 9 WhoisJSON API plans and prices →
WhoisJSON API fact sheet
| Free plan | Yes |
|---|---|
| Paid from | $10/mo |
| API access | Not verified |
| Bulk lookup | Not verified |
| Historical WHOIS | Not verified |
| RDAP support | Not verified |
| Monthly lookup limit | Not verified |
| Export formats | Not verified |
| Deployment | Cloud |
| Compliance & security | GDPR |
| Support | Docs |
| Built for | Solo, Small business, Mid-market, Enterprise (editorial estimate) |
| Integrations | 6 integrations: PHP, Python, Node.js, Claude, Cursor, Windsurf |
| Pricing | Free plan (source) |
| Website | whoisjson.com |
| Facts checked | 20 Sep 2026 |
WhoisJSON API integrations
WhoisJSON API lists 6 integrations on its own site.
- PHP
- Python
- Node.js
- Claude
- Cursor
- Windsurf
Alternatives to WhoisJSON API
- WhoisDataCenterA broad WHOIS research service with useful free allowances and paid data products.9.4
- WhoisXML API WHOIS APIA broad lookup API with RDAP, parsed data, integrations, and a free tier.9.2
- WhoxyA pay-as-you-go WHOIS platform for high-volume lookups, history, reverse search, and datasets.9.0
See all WhoisJSON API alternatives →
WhoisJSON API vs the competition
- WhoisJSON API vs WhoisDataCenter
- WhoisJSON API vs WhoisXML API WHOIS API
- WhoisJSON API vs Whoxy
- WhoisJSON API vs WhoisFreaks WHOIS API
- WhoisJSON API vs OpenRDAP
- WhoisJSON API vs RDAP API
Compare WhoisJSON API with any tool side by side →
Also Ranked In
WhoisJSON API is ranked in 2 of our directories.
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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
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