WhoisFreaks Reverse WHOIS API review
A developer-ready reverse WHOIS API with historical searches, SDKs, and workflow integrations.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
WhoisFreaks Reverse WHOIS API is a paid API for finding domains associated with email addresses, registrant names, company names, and domain keywords. Its historical WHOIS searches return paginated results in JSON or XML, making it relevant to security investigations, brand protection, domain portfolio analysis, threat intelligence, competitive research, and due diligence. The product is particularly suited to developer teams that need reverse WHOIS data inside applications, scripts, or automated workflows rather than through a standalone visual search interface.
Pricing is structured around API credits. The Monthly Subscription costs $75 per month and includes 50,000 API credits; unused credits expire after one month. The Yearly Subscription costs $1,500 per year and includes 50,000 API credits per month, with credits expiring after one year. The API Credits option costs $150 one time for 50,000 credits, and those credits do not expire. There is no free plan, so teams should select a credit model based on whether usage is recurring, annual, or occasional. The published plans also show different expiration rules, which matter when estimating how much of an allocation can be used over time.
The API’s strongest fit is its combination of search depth and integration coverage. In addition to exact and pattern-based email searches, it supports historical records, pagination, and wildcard or regex-style email matching. Official SDKs cover Python, JavaScript, TypeScript, Java, Kotlin, C#/.NET, Ruby, Go, and Swift, while workflow connections include Microsoft Security Copilot, Make, MISP, MCP Server, Postman, and n8n. Choose it when reverse WHOIS data needs to feed developer tools, investigations, or automated processes. Consider an alternative if you need a free evaluation tier or a browser-first product experience.
WhoisFreaks Reverse WHOIS API pros and cons
- Where it wins
- Search by email, registrant name, company, or domain keyword
- Historical WHOIS data with wildcard and regex-style email matching
- JSON/XML output, SDKs, and integrations for developer workflows
- Where it doesn't
- No free plan for evaluating the API
- Unused monthly credits expire after one month
- API-only access may not suit users seeking a visual interface
WhoisFreaks Reverse WHOIS API fact sheet, pricing and score →
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