Bulk WHOIS Lookup of 500K domains simultaneously | WhoisXML API
Contact Us
Bulk API docs FAQ Pricing Order now

Bulk WHOIS Lookup lets you look up thousands of domain owners in one go

Are you in need of WHOIS domain intelligence but don’t have the time to look up domains one by one? Get the ownership details of up to 500,000 domains at one time with our bulk domain lookup tool.

Upload a file
Input as text
Input file example: sample.csv Data source requirements & rules
Bulk WHOIS API

What is a bulk WHOIS lookup?

A bulk WHOIS lookup is a means to get details that include registrant name, organization, contact email address, and much more with a single query. Just upload a comma-separated values (CSV) file containing the list of domains you want information on or copy and paste the list into the input box and wait for your results.

Our bulk WHOIS lookup tool is:

  • Always on

    Bulk WHOIS Lookup is a web-based service that you can access anytime you need to query a list of domains for ownership data. All you need is a WhoisXML API subscription to get the results you require.

  • Backed by one of the biggest WHOIS databases

    Our bulk WHOIS lookup tool pulls data from a domain database that contains more than 7 billion WHOIS records that cover 2,864+ top-level domains (TLDs).

  • Robust

    Every bulk domain lookup you make is sure to get the latest registrant information as our WHOIS database gets daily updates. That assures you of relevant and timely data for your business needs.

  • Flexible

    Bulk WHOIS Lookup lets you choose between uploading a CSV file or copying and pasting your list into the interface when making queries.

Practical usage

Cybersecurity

Cybersecurity

  • Look up all domains related to an email or IP address when investigating a potential crime or an ongoing attack with our bulk domain WHOIS tool.
  • Know everything there is to know about a domain of interest, including the registrant’s name, organization, address, and more, when you’re building an attack profile with a simple bulk domain lookup.

Domain research and monitoring

  • Follow every move competing domainers make. The list of domains that you get from a bulk domain lookup should clue you into emerging trends you may be missing out on.
  • Track modifications made to your domain portfolio with a bulk domain WHOIS query. Some of them may have been unauthorized and need to be addressed immediately.
Domain research and monitoring
Marketing and sales

Marketing and sales

  • Ensure you don’t miss out on any online infrastructure changes your customers make. Constantly update your contact list with bulk WHOIS lookups.
  • Get to know your clients and stakeholders better by looking at their digital footprints. You may find untapped sales opportunities with deeper digs via bulk domain lookups into their lines of business.

Brand protection and fraud prevention

  • Make sure you are dealing with legitimate users from your client list through a bulk domain lookup. Compare their credentials with those of their supposed organizations that you keep on record.
  • Keep your contact list up-to-date with regular checks on our bulk domain WHOIS tool that’s updated daily.
Brand protection and fraud prevention

Integrate Bulk WHOIS API for faster results

Bulk WHOIS API gives the same results but is integrable into existing systems and solutions so you can get what you’re looking for faster and use the information immediately. Sample codes for the commonly used languages (C#, JavaScript, PHP, etc.) are available.

Learn more about Bulk WHOIS API

Trusted by
the smartest
companies

You may be interested

Reverse WHOIS
Reverse WHOIS

Find connections between various domains, individuals and organizations.

Learn more
Screenshot Service
Screenshot Service

Instantly get a screenshot of any web page.

Learn more
IP Netblocks
IP Netblocks

Find out which IP range the particular IP belongs to.

Learn more
Real-time Domain Registration
Real-time Domain Registration

Get data feeds of new registered domains along with their WHOIS data generated in real time.

Learn more
Domain Reputation API
Domain Reputation API

Assess the domain's or IP addresses reputation and risk profile with a simple score based on a comprehensive...

Learn more
Registrant Alert
Registrant Alert

Find out which domains were added or dropped by registrants, with given search criteria.

Learn more
DNS Lookup Services
DNS Lookup Services

Identify who is hosting a particular domain name or website.

Learn more
Typosquatting Data Feed
Typosquatting Data Feed

Easily detect all typosquatting domain names as soon as they are registered each day.

Learn more
Website Categorization
Website Categorization

Define website category of the given domain.

Learn more
Reverse MX
Reverse MX

Reveal all the domains that use the same mail server.

Learn more
Domain Availability
Domain Availability

The most accurate domain availability checker offered on the market.

Learn more
IP Geolocation
IP Geolocation

Find out the exact physical location of any IP address, email or domain name.

Learn more
WHOIS Search
WHOIS Search

Get well-parsed and normalized WHOIS information for any domain name, IP address or email.

Learn more
WHOIS Database Download
WHOIS Database Download

We provide complete and relevant domain WHOIS data which can be customized and easily integrated as per your business needs.

Learn more
All Registered Domains
All Registered Domains

Get a complete daily list of all the registered domains and zone files.

Learn more
Brand Alert
Brand Alert

Monitor exact matches, variations and common misspellings of your brand name & trademarks.

Learn more
Newly Registered Domains
Newly Registered Domains

Keep track of the best business opportunities online.

Learn more
Website Contacts
Website Contacts

Get full contacts data of the given domain.

Learn more
US Internet Retailers Database
US Internet Retailers Database

Get access to the biggest US Internet Retailers Database.

Learn more
Subdomains Lookup
Subdomains Lookup

Discover subdomains related to the target domain name.

Learn more
Email Verification
Email Verification

Ensure the validity and quality of any email address.

Learn more
Threat Intelligence Data Feeds
Threat Intelligence Data Feeds

Get the most relevant data to be ahead of emerging security threats.

Learn more
Reverse IP/DNS
Reverse IP/DNS

Find relations like ownership between hostnames and IPs.

Learn more
Domain Research Suite
Domain Research Suite

Enhance your domain research toolkit by our enterprise-grade web-based solution that helps you in searching...

Learn more
Reverse NS
Reverse NS

Find all domains that use the same name server.

Learn more
Have questions?

We are here to listen. For a quick response, please select your request type or check our Contact us page for more information. By submitting a request, you agree to our Terms of Service and Privacy Policy.

Or shoot us an email to