Provide current and historical ownership information on domains / IPs. Identify all connections between domains, registrants, registrars, and DNS servers.
Look into all current and historical DNS / IP connections between domains and A, MX, NS, and other records. Monitor suspicious changes to DNS records.
Get detailed context on an IP address, including its user’s geolocation, time zone, connected domains, connection type, IP range, ASN, and other network ownership details.
Access our web-based solution to dig into and monitor all domain events of interest.
Get access to a web-based enterprise-grade solution to search and monitor domain registrations and ownership details for branded terms, fuzzy matches, registrants of interest, and more.
Detect and block access to and from dangerous domain names before malicious actors can weaponize them. Contact us today for more information.
Unlock integrated intelligence on Internet properties and their ownership, infrastructure, and other attributes.
Our complete set of domain, IP, and DNS intelligence available via API calls as an annual subscription with predictable pricing.
Offers complete access to WHOIS, IP, DNS, and subdomain data for product enrichment, threat hunting and more.
Enjoy priority data access with our premium API services topped with extra perks including dedicated team support, enterprise-grade infrastructure, and SLAs for full scalability and high performance.
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Learn MoreReverse WHOIS is the process by which users can find all domains containing specified search terms such as a registrant's name, email address, or phone number in their WHOIS records.
Find all domain names with the same owner information anywhere in their WHOIS records. Check which domains, individuals, and organizations are connected.
Get the entire registration details or WHOIS record of domains associated with your search terms. You can tailor your request by searching using specific attributes.
Searched domains can be monitored for any registration changes by adding them to Domain Monitor.
Reverse WHOIS data can help identify dangerous domain footprints linked to a cybercriminal, scammer, or spammer. It can be used in combination with WHOIS history capabilities to study historical domain connections.
Learn more about business prospects, partners, competitors, and their current activities by finding domain names connected to them as well as all corresponding WHOIS information.
With a WHOIS search by registrant name, you can uncover the domain portfolio of individuals and organizations infringing your trademarks with confusingly similar domains.
You can also search WHOIS by domain owner’s details via API calls. It’s easy to build reverse domain search capabilities with our integration options and code libraries.
Learn more about API integration“The WhoisXML History API has been a game changer for our online investigations, trainings, and books. We have uncovered the true owners behind numerous malicious domains, even though they currently possess "private" Whois registration.”
“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.”
“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.”
“The consistent and structured data provided by WhoisXML API made it possible to group and identify who is behind suspected fraudulent websites, being able to search by phone number, address or e-mail address used in the domain registration.”
“I appreciate your products that are useful for checking domain expiration dates.”
“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.”
“DRS is a Great product, easy to use and everything I need in one place.”
“Very useful for investigations, we can go back in history and see when domains were registered and who owned them at a certain time.”
“WhoisXML API builds out data sets that help users correlate attack infrastructure with related IP and WHOIS information.”
Sign up now for access to Reverse WHOIS Search and the Domain Research Suite (DRS).
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