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

With one API call, for search terms such as a domain owner’s name, email address, phone number, or postal address, you will get a list of all the linked domains that contain the identifier.

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500 free API credits. No credit card required.

774 Million+Domains tracked

25.5 Billion+WHOIS records

7,596+TLDs and ccTLDs tracked

52,000+Satisfied customers

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 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’s WHOIS record. For example, search by registrant email address or name.
Get consistently formatted and structured WHOIS information for easy comparison with your existing databases.
Get Current as well as Historic Reverse WHOIS data.
Result options include popularly used Extensible Markup Language (XML) and JavaScript Object Notation (JSON).
Your search term can be an exact or a fuzzy match. For example, you may search for any registrant name that starts with the term “John” or any registrant email address that contains the term “xyz.”
With regularly updated WHOIS data, you’re sure to get only the latest information.

Practical usage

Protection for brands

Brand protection professionals can safeguard their crown jewels by alleviating potential trademark infringements with reverse WHOIS data. Reverse WHOIS API catches domain lookalikes or copycats.

Cybersecurity enhancement

Researchers can rely on Reverse WHOIS API in combination with a WHOIS history viewpoint to investigate and eventually thwart cybercrime. Meanwhile, integration into antimalware solutions can detect spam, malicious links, attack attempts, and other misdeeds.

Online fraud detection

Reverse WHOIS API helps payment processors, banks, and other financial institutions prevent transaction fraud. Website owners and administrators can use it to scout for legitimate business and partnership opportunities using the contact details that domain owners reveal in their WHOIS records.

Policing the Web

Reverse WHOIS API or Reverse WHOIS Search is an investigation must-have for law enforcement agents who wish to map out attackers’ infrastructure. Find all domains, websites, IP addresses, and more details connected to a crime or criminal with the tool’s help.

Market research

Reverse WHOIS API benefits business owners on the lookout for expansion. Use it to find new customers, too, through the contact details you can get from the WHOIS database.

Get 500 free API credits. No credit card required.

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Kim Kok

Vice President

Core4ce

“We want to provide all Cyberscape users the ability to integrate relevant data for their cyber threat investigations. WhoisXML API provides unique data that will be helpful to the cyber threat investigation community, allowing analysts to shorten the cycle of understanding and mitigating threats.”

Flavio Critelli

Distinguished Professor of Digital Forensics

University of Perugia

“Whois XML is one of the most important tools we use for domain intelligence in the Bachelor's Degree program in Investigation and Security Sciences at the University of Perugia. In particular, we appreciate the reverse research from IP to Domain and Whois with query filters. The tool is comprehensive, providing detailed information such as phone numbers, names, and other details from Whois records. While many Whois records are now covered by privacy regulations, WhoisXML API provides access to all historical WHOIS records.”

Michael Roberts

Founder & Private Investigator

Rexxfield

“WhoisXML was the game changer for us. It has revolutionized our ability to disrupt cybercrime in process and at scale by quickly identifying all of the vendors providing material support for scammers using sophisticated website templates that look legitimate. By quickly identifying the vendors unknowingly supporting the criminals, we can provide them with public interest justification to burn down the criminal infrastructure.”

Larry Cameron

President and Founder

Paradigm Intelligence Ltd

“WhoisXML API is amazing for checking out the historic registration information of a domain, pivoting to locate the alternate registrations with the same details and also my cyber investigations. The data proved very useful when investigating pig butchering scams and domains that host child abuse material.”

Jacob Waltz

CEO/Founder

Intraframe

“Very useful for investigations, we can go back in history and see when domains were registered and who owned them at a certain time.”

David Pearson

CEO/Founder

Bayse Intelligence

“WhoisXML API builds out data sets that help users correlate attack infrastructure with related IP and WHOIS information.”

WHOIS / WHOIS History

DNS / DNS History

IP Geolocation / IP Netblocks

Domain/WHOIS

DNS/IP

Intelligence

Other

Domain/WHOIS

DNS/IP

Intelligence

Other

Domain/WHOIS

DNS/IP

Intelligence

Other

Research

Monitoring

White-Label

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

Benefits

Practical usage

Protection for brands

Cybersecurity enhancement

Online fraud detection

Policing the Web

Market research

Get 500 free API credits. No credit card required.

Trusted by the smartest companies

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