Get bulk access to parsed Domain WHOIS ownership information for a list of domains / IPs of your choice.

WHOIS database List of WHOIS records Domains/IPs list

Bulk Whois API provides Whois records for a bulk list of domains/IPs via a single REST API query. Get key data points for domains, including registrant name, organization, e-mail address, registration address, registrar information, creation date, expiration date, updated date, domain availability, domain age, and more. All of the WHOIS information is well-parsed and normalized to a consistent format for easy integration with your business processes.

6.7+ billion Historic WHOIS Records
1.2+ billion Domains and subdomains
2,864+ TLDs & ccTLDs
52K+ Satisfied customers


  • Provides Whois records in bulk for a large number of domain names or IP addresses.
  • Flexibility to upload multiple domain list files and getting separate Unique/Request ID for each list provided.
  • The query results with both parsed fields and raw texts are returned in popular XML & JSON format.
  • Get key data points for domains including registrant name, organization, e-mail address, registration address, registrar information, creation date, expiration date, updated date, domain availability, domain age, and more.
  • All of the Whois information is well-parsed and normalized to a consistent format for easy integration with your business processes.

Practical Uses

Cyber security

Cyber Security researchers use Bulk Whois lookup API for investigating & curbing cybercrime.


Payment processors and banks use Bulk Whois lookup API to detect transaction fraud.

Domain names monitoring

Registrars & Domainers need Bulk Whois lookup API to keep track of domains.

Brand protection

Brand agents use the Whois lookup API to protect their intellectual property and check potential trademark infringements through random searches to reduce and eliminate domain name similarities, duplicates, or copycats.

Law enforcement

Law enforcement agencies depend on Bulk Whois lookup API for background checks in investigations.


Marketing Researchers use Bulk Whois lookup API to research domain details either for specific brand purpose or otherwise.

There are numerous other domain research / monitoring usages across other industries.

Who we are & our Bulk WHOIS Lookup API service

WhoisXML API is a large data and API company that offers services with regard to Whois, IP, domain and DNS, as well as threat intelligence data. The organizations served by the company span far and wide; they include government agencies, cyber security firms, brand agents, online payment processors and domain brokers and investors. We provide Bulk Whois API records and domain and multiple domain list files uploading service. Since its establishment in 2010, the firm has continually focused on expanding its delivery and reach through strategic alliances and acquisitions. To ensure customer satisfaction, WhoisXML API offers numerous incentives to its wide client base.

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Enterprise API Packages

API access through WhoisXMLAPI can be purchased as an annual subscription. The access pricing is based on the number of queries, which is measured monthly with per-minute rate limits. The pricing structure gives predictability to business planning and solution architecture.

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Whois Lookup API end-user solutions

The information offered by WhoisXML API has numerous practical uses with huge disruptive effects across various industries. Cybersecurity researchers will find the Bulk Whois lookup API offered by WhoisXML API absolutely essential for interrogating and curbing cyber crimes as well as creating powerful and up-to-date cyber security and anti-malware solutions. The cyber security solutions can tap into Whois API resource-rich database to detect malicious websites, spam, unauthorized intrusions and other online activities that may compromise data integrity. Already, many payment processors and financial institutions are using the Whois API to detect fraud and other forms of financial improprieties. Law enforcement agencies together with the local and national security apparatus can also use Whois data to accurately identify connected domains, IP addresses, and websites that may be used to permeate crime and fraud.

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Downloading and paying for Bulk Whois Lookup API services

Downloading Bulk Whois API data with WhoisXML API is easy once you decide the type of data you need and pick the most appropriate format for software tools and download. For data download subscription, users can choose between daily and quarterly data feeds. The quarterly data are organized into lengthy 3-month releases based on database versions while the daily feeds usually reflect the daily changes in domain registrations. For the huge, Bulk Whois lookup API datasets, WhoisXML API can help users review the infrastructure setup. However, to perform the review more efficiently and avoid unnecessary delays, significant memory and CPU resources are required.

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Get in touch with Bulk Whois Lookup API pros

WhoisXML API is trusted by more than 52,000 clients who include “Who is Who” is the tech world. The brands topping the list include Apple, Amazon, EBay Cisco and AT&T. In terms of size, the system operated by the company’s register supports close to 3,000 Top Level Domains (TLDs); this includes Country Code Top-Level Domains (ccTLDs) and Generic Top-Level Domains (gTLDs). Clients can choose the Reverse Whois API 2.0 solution to identify domains related to an individual or business and see how they are interconnected. Note that generous restrictions apply to the usage limit and number of domain allowed in each query.

Since its establishment 9 years ago, WhoisXML API has tracked over 300 million domains and searched more than 5 billion records. To facilitate payments, the reputable and trusted online API offers convenient online payment options. More importantly, WhoisXML API offers competitive customer service, which ensures all queries are unhindered and answered in good time. For expedite support, a special email address is provided for reporting support issues, generalized inquiries, and customized Whois services or products. A dedicated phone number is also available for non-urgent service catering for enterprise customers.

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