Registrant Alert API | WhoisXML API

Search across all registered and dropped domain names for the registrant's specific details

Registrant Alert API is ideal for monitoring specific domain registrants to be alerted whenever their information is linked to a newly-registered or just-expired domain name.

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500 free API credits. No credit card required.

774 Million+Domains tracked
21.0 Billion+WHOIS records
7,596+TLDs and ccTLDs tracked
52,000+Satisfied customers


  • Precise

    Helps you set up program to receive notifications whenever specified individuals or organizations register or delete domains.You can backtrack the alerts by setting the sinceDate request parameter.

  • Catchall

    The Registrant Alert API searches new .com, .net, .org, .biz, .mobi, .us, .pro, .coop, .asia and thousands of gTLDs and ccTLDs for your specified registrant or terms.

  • Flexible

    Search results can be filtered based on registration or expiration date. For example, if you want records only within the last year, you can do that.

  • Up-to-date

    By default, the result contains all the domain names registered or dropped on the most recent day. Your program can monitor each set of terms by submitting a single query each day.

Practical usage

Brand Protection

Brand Protection

Protect your brand against potential abuse by continuously monitoring across all registered and dropped domain names correlated with your brand, for specific search terms such as the registrant's details and more.

Domain names monitoring

Registrars and Domainers can use this product to keep track of domain registrations and monitor domain ownership changes.

Domain names monitoring
Registrant Alert API | WhoisXML API

Get 500 free API credits. No credit card required.

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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

API access through WhoisXMLAPI can be purchased as an annual subscription. The access pricing is based on the number of queries, which is measured monthly with per-minute rate limits. The pricing structure gives predictability to business planning and solution architecture.

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