WHOIS API | 374M+ active domains & 7,596 TLDs tracked | WhoisXML API

WHOIS API offers unified & consistent data

Our hosted WHOIS API service provides the registration details, also known as the WHOIS record data, of a domain name, an IP address, or an email address. All of the WHOIS information we offer is adequately parsed and normalized to a consistent format so it can easily fit in with your business operations.

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What is WHOIS API?

WHOIS API is a consumption model variant that gathers a variety of domain ownership and registration data points from a comprehensive WHOIS database. Developers can integrate WHOIS API into existing internal systems and commercial applications using client libraries and integration modules.

  • Comprehensive across TLDs

    Our WHOIS repository contains information from millions of active domain and subdomain records that cover more than 7,596 generic (gTLDs) and country-code top-level domains (ccTLDs) and second-level domains (ccSLDs).

  • Unified and fit for purpose

    Our WHOIS data can be quickly integrated into different internal systems to speed up its use by various stakeholders.

  • Handy

    Need data viewable in either Extensible Markup Language (XML) or JavaScript Object Notation (JSON)? Our API provides both output types.

  • Reliable and current

    Our WHOIS data is gathered in near-real-time, giving you exclusive access to accurate and updated information for better decision-making.

Practical usage

Cybercrime prevention

Digital forensics and incident response (DFIR) and other cybersecurity consultants can rely on WHOIS API to provide clients with easy-to-read lists of domains that may have ties to cybercrime, thus allowing them to enhance their cyber defense. This information could be particularly useful in mitigating phishing and other malware-enabled attacks.

Cybercrime prevention

Investigating and curbing cybercrime

Infosec professionals can work with WHOIS API to enhance their solutions and services and protect users against spam, dangerous websites, network infiltrations, and other online misdeeds as well as to investigate third-party risks.

Law enforcement

Law enforcement agents can use WHOIS API as a tool for investigations to find IP addresses, websites, and domains sharing attributes with criminals’ online networks.

Monitoring domain changes

Monitoring domain changes

Domainers can determine if a domain name is available and keep up with registration changes by working with WHOIS API. They can see all historical changes to particular domains with a simple search while the monitoring functionality lets them stay updated on the most recent domain changes.

Domain appraisal

Domain investors find WHOIS information helpful when tracking the competition and looking for new investment opportunities.

Domain transfer

Domain brokers and registrars can rely on WHOIS API to efficiently manage domain name ownership transfers.


DevOps professionals can use WHOIS data to build new features and enrich other data sources as part of their software development and IT operations.

Payment processing

Payment processors and banks can prevent transaction fraud by looking out for customer information discrepancies and thwart malicious actors with the help of WHOIS API.

Payment processing
Social sciences

Marketing research

WHOIS API simplifies marketing research by allowing you to gather domain ownership information for statistical analyses. It also helps you make tailor-fit marketing strategies and campaigns for various user bases and identify otherwise-untapped opportunities.

Brand protection

WHOIS data enables brand agents to spot potential instances of trademark infringement like using blatantly similar, copycat, or duplicate domain names. This information can also be used with Website Categorization products to gather greater context around a domain.


Know your customers and prospects better with WHOIS API’s domain ownership information. Make your outreach efforts easier by using the contact details in domain records.

Download an exhaustive WHOIS database for your business needs

Our database comes in the form of CSV files and MySQL dumps for maximum compatibility and fast integration into existing systems.

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Simplify your work

WHOIS API Splunk application tutorial WHOIS API WordPress plugin bestwhois - a command-line whois-like client

We provide extensions for major open-source threat intelligence platforms. Integrate WHOIS API into your applications in minutes.

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Premium API Services

Our APIs are available in an enhanced version that offers better performance with a dedicated load balancer and a premium endpoint to enable faster throttling for large-scale API deployments.

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Enterprise API Packages

Do much more with our annual API subscriptions that cover WHOIS data and other types of domain, IP, and DNS intelligence. See how we can match your business planning and solution architecture requirements.

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