Reverse WHOIS Lookup by a domain owner’s name, etc. | WhoisXML API

Reverse WHOIS Lookup: List all domains linked by an owner’s name, an email address, or other WHOIS detail

With a registrant’s name, a company name, an email address, or other search terms on hand, you can find all domain names that contain the queried term in their WHOIS records.

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

What Is a Reverse WHOIS Lookup?

A reverse WHOIS lookup is a means to retrieve all domain names containing your search term in their WHOIS records. With just a single piece of information, you can already retrieve relevant domains to get more insights for cybercrime investigations, market research, and threat hunting efforts.

Reverse WHOIS Lookup

Why use Reverse WHOIS Lookup?

  • Accurate

    Reverse WHOIS Lookup calls data from a WHOIS database that gets updated daily to ensure data accuracy and relevance.

  • Comprehensive

    Our WHOIS database contains more than 7 billion historical WHOIS records — a result of over a decade of data crawling.

  • Flexible

    You can choose any WHOIS record detail as a search term to pool all related domains.

  • Easy to use and share

    Reports from Reverse WHOIS Lookup come with unique URLs, allowing you to share them with colleagues and relevant stakeholders easily.

Practical usage of a reverse domain lookup tool

Deepen cybercrime investigations

Deepen cybercrime investigations

  • All cybercriminals leave digital breadcrumbs behind. Use them to list all related domain names that can uncover ties to specific attackers or campaigns. Combine results with those from other tools such as DNS Lookup, Reverse IP/DNS Lookup, Reverse MX Lookup, and Reverse NS Lookup for even more exhaustive findings.
  • Create attack profiles with just an attacker’s name, alias, email address, or phone number. Reverse WHOIS Lookup lets you retrieve associated domains that could make up a cybercriminal’s infrastructure.

Improve threat hunting efforts

  • Add one more data source to your threat intelligence sources. List all domain names connected to a campaign, threat actor, or criminal enterprise.
  • Identify other unreported threat sources using known indicators of compromise (IoCs) as search terms.
Improve threat hunting efforts
Enhance brand protection strategies

Enhance brand protection strategies

  • Check out potential trademark infringers by using your brand or trademark as a search term. For even more details, use Reverse WHOIS API or Reverse WHOIS Search.
  • Catch copycats and fraudsters red-handed by using a known threat actor’s name as a search term. Reverse WHOIS lookups can improve your cybersquatting protection efforts and help you gather evidence for litigation.

From one or several unique identifiers and terms present in a WHOIS record, get a list of all connected domain names with our new Domain Research Suite (DRS) dashboard.

Fast, intuitive and responsive.

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Reverse WHOIS Search | Domain Research Suite | WhoisXML API
Reverse WHOIS Lookup | WhoisXML API

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