Reverse WHOIS API | Whois XML API

Find all domain names which contain a specified search terms in their WHOIS records

With the one API call containing search terms such as name, email, phone, address, etc. you will get a list of all the domain records that correspond to the search terms used.

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100 free credits monthly. No credit card required.

7.0+ billion Historic WHOIS Records
582+ million Domains tracked
2,864+ TLDs tracking
10+ years of data crawling

Benefits

  • Discover all domain names associated with an individual or an organization. Find connections between various domains, individuals and organizations.

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

  • You may search by specific attributes in the Domain WHOIS Records. For example, search by registrant email/ registrant name.

  • All of the WHOIS information is well-parsed and normalized to a consistent format for easy integration with your business processes.

  • Get Current as well as Historic Reverse WHOIS data.

  • The query results are returned in popular XML & JSON formats.

  • Your search term can be an exact match or fuzzy match. For example, you may search for any registrant name that starts with the term "John", or search for any registrant email address that contains the term "xyz".

  • Real-time WHOIS data ensures that only the most up-to-date and accurate information is delivered.

Practical usage

Brand Protection

Brand Protection

Brand agents use Reverse WHOIS data to protect their intellectual property and check for potential trademark infringements through searches to scope domain name similarities, duplicates, or copycats.

Cyber Security

Researchers use Reverse WHOIS API for investigating & curbing cybercrime. Cyber Security and antimalware solutions use Reverse WHOIS API to detect spam, malicious websites, intrusions, and other online misbehaviors.

Cyber Security
Cyber Fraud Detection

Cyber Fraud Detection

Payment processors and banks use Reverse WHOIS API to detect transaction fraud. Website owners and managers use Reverse WHOIS API to identify new business and partnership opportunities and to locate potential buyers through the contact details provided in the WHOIS database.

Law Enforcement

Law enforcement agencies use Reverse WHOIS API to identify all of the connected domains, websites and IP addresses associated with fraudulent activities and criminals.

Law Enforcement
Marketing research

Marketing research

Website owners and managers use Reverse WHOIS API to identify new business and partnership opportunities and to locate potential buyers through the contact details provided in the WHOIS database.

By using one or more unique identifiers or terms found in a WHOIS record, find all the domain names related to it with our new Domain Research Suite Dashboard.

Fast, intuitive and responsive

Get started
Reverse WHOIS Search | Domain Research Suite | Whois XML API
Reverse WHOIS API | Whois XML API

Get 100 free credits monthly. No credit card required.

Get started

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