Reverse WHOIS API: Find Every Domain Tied to an Identity

Standard WHOIS lookup tells you who owns a domain. The WhoisFreaks Reverse WHOIS API flips that question - give it an email address, registrant name, company, or keyword and it returns every domain in our 3.6B+ record database connected to that identifier. Paginated, structured, and available in JSON or XML.

curl --location --request GET 'https://api.whoisfreaks.com/v1.0/whois?whois=reverse&keyword=whoisfreaks&apiKey=API_KEY'

[
  {
    "total_Result": 3,
    "total_Pages": 1,
    "current_Page": 1,
    "whois_domains_historical": [
      {
        "num": 1,
        "status": true,
        "domain_name": "whoisfreaks.com",
        "query_time": "2024-04-02 17:45:50",
        "whois_server": "whois.verisign-grs.com",
        "create_date": "2019-03-19",
        "update_date": "2024-02-18",
        "expiry_date": "2025-03-19",
        "domain_registrar": {
          "iana_id": "1068",
          "registrar_name": "namecheap, inc.",
          "whois_server": "whois.namecheap.com",
          "website_url": "http://www.namecheap.com",
          "email_address": "[email protected]",
          "phone_number": "+1.9854014545"
        },
        "reseller_contact": {
          "name": "NAMECHEAP INC",
          "email_address": "N/A",
          "phone": "N/A"
        },
        "registrant_contact": {
          "name": "Redacted for Privacy",
          "company": "Privacy service provided by Withheld for Privacy ehf",
          "street": "Kalkofnsvegur 2",
          "city": "Reykjavik",
          "state": "Capital Region",
          "zip_code": "101",
          "country_name": "Iceland",
          "country_code": "IS",
          "email_address": "[email protected]",
          "phone": "+354.4212434",
          "fax": "N/A",
          "mailing_address": "Kalkofnsvegur 2, 101 Reykjavik, Capital Region, Iceland"
        },
        "administrative_contact": {
          "name": "Redacted for Privacy",
          "company": "Privacy service provided by Withheld for Privacy ehf",
          "street": "Kalkofnsvegur 2",
          "city": "Reykjavik",
          "state": "Capital Region",
          "zip_code": "101",
          "country_name": "Iceland",
          "country_code": "IS",
          "email_address": "[email protected]",
          "phone": "+354.4212434",
          "fax": "N/A",
          "mailing_address": "Kalkofnsvegur 2, 101 Reykjavik, Capital Region, Iceland"
        },
        "technical_contact": {
          "name": "Redacted for Privacy",
          "company": "Privacy service provided by Withheld for Privacy ehf",
          "street": "Kalkofnsvegur 2",
          "city": "Reykjavik",
          "state": "Capital Region",
          "zip_code": "101",
          "country_name": "Iceland",
          "country_code": "IS",
          "email_address": "[email protected]",
          "phone": "+354.4212434",
          "fax": "N/A",
          "mailing_address": "Kalkofnsvegur 2, 101 Reykjavik, Capital Region, Iceland"
        },
        "billing_contact": {
          "name": "N/A",
          "company": "N/A",
          "street": "N/A",
          "city": "N/A",
          "state": "N/A",
          "zip_code": "N/A",
          "country_name": "N/A",
          "country_code": "N/A",
          "email_address": "N/A",
          "phone": "N/A",
          "fax": "N/A",
          "mailing_address": "N/A"
        },
        "name_servers": [
          "dns8.cloudns.net",
          "dns4.cloudns.net",
          "dns3.cloudns.net",
          "dns7.cloudns.net"
        ],
        "domain_status": [
          "clientTransferProhibited"
        ],
        "registry_data": {
          "domain_name": "WHOISFREAKS.COM",
          "query_time": "2024-04-02 17:45:50",
          "whois_server": "whois.verisign-grs.com",
          "create_date": "N/A",
          "update_date": "N/A",
          "expiry_date": "N/A",
          "domain_registrar": {
            "iana_id": "1068",
            "registrar_name": "NameCheap, Inc.",
            "whois_server": "whois.namecheap.com",
            "website_url": "http://www.namecheap.com",
            "email_address": "[email protected]",
            "phone_number": "+1.6613102107"
          },
          "name_servers": [
            "dns8.cloudns.net",
            "dns4.cloudns.net",
            "dns3.cloudns.net",
            "dns7.cloudns.net"
          ],
          "domain_status": [
            "clientTransferProhibited"
          ]
        }
      },
      {
        "num": 2,
        "status": true,
        "domain_name": "whoisfreaks.org",
        "query_time": "2024-04-03 15:22:45",
        "whois_server": "whois.pir.org",
        "create_date": "2023-03-04",
        "update_date": "2024-01-27",
        "expiry_date": "2025-03-04",
        "domain_registrar": {
          "iana_id": "303",
          "registrar_name": "pdr ltd. d/b/a publicdomainregistry.com",
          "whois_server": "http://whois.publicdomainregistry.com",
          "website_url": "http://www.publicdomainregistry.com",
          "email_address": "[email protected]",
          "phone_number": "+1.2013775952"
        },
        "registrant_contact": {
          "name": "REDACTED FOR PRIVACY",
          "company": "N/A",
          "street": "REDACTED FOR PRIVACY",
          "city": "REDACTED FOR PRIVACY",
          "state": "Other",
          "zip_code": "REDACTED FOR PRIVACY",
          "country_name": "India",
          "country_code": "IN",
          "email_address": "please query the rdds service of the registrar of record identified in this output for information on how to contact the registrant, admin, or tech contact of the queried domain name.",
          "phone": "REDACTED FOR PRIVACY",
          "fax": "REDACTED FOR PRIVACY",
          "mailing_address": "India"
        },
        "administrative_contact": {
          "name": "REDACTED FOR PRIVACY",
          "company": "REDACTED FOR PRIVACY",
          "street": "REDACTED FOR PRIVACY",
          "city": "REDACTED FOR PRIVACY",
          "state": "REDACTED FOR PRIVACY",
          "zip_code": "REDACTED FOR PRIVACY",
          "country_name": "REDACTED FOR PRIVACY",
          "country_code": "N/A",
          "email_address": "please query the rdds service of the registrar of record identified in this output for information on how to contact the registrant, admin, or tech contact of the queried domain name.",
          "phone": "REDACTED FOR PRIVACY",
          "fax": "REDACTED FOR PRIVACY",
          "mailing_address": "N/A"
        },
        "technical_contact": {
          "name": "REDACTED FOR PRIVACY",
          "company": "REDACTED FOR PRIVACY",
          "street": "REDACTED FOR PRIVACY",
          "city": "REDACTED FOR PRIVACY",
          "state": "REDACTED FOR PRIVACY",
          "zip_code": "REDACTED FOR PRIVACY",
          "country_name": "REDACTED FOR PRIVACY",
          "country_code": "N/A",
          "email_address": "please query the rdds service of the registrar of record identified in this output for information on how to contact the registrant, admin, or tech contact of the queried domain name.",
          "phone": "REDACTED FOR PRIVACY",
          "fax": "REDACTED FOR PRIVACY",
          "mailing_address": "N/A"
        },
        "billing_contact": {
          "name": "N/A",
          "company": "N/A",
          "street": "N/A",
          "city": "N/A",
          "state": "N/A",
          "zip_code": "N/A",
          "country_name": "N/A",
          "country_code": "N/A",
          "email_address": "N/A",
          "phone": "N/A",
          "fax": "N/A",
          "mailing_address": "N/A"
        },
        "name_servers": [
          "dns3.bigrock.in",
          "dns2.bigrock.in",
          "dns1.bigrock.in",
          "dns4.bigrock.in"
        ],
        "domain_status": [
          "clientTransferProhibited"
        ]
      },
      {
        "num": 3,
        "status": true,
        "domain_name": "whoisfreaks.in",
        "query_time": "2024-01-29 11:08:45",
        "create_date": "2023-03-04",
        "update_date": "2024-01-27",
        "expiry_date": "2025-03-04",
        "domain_registrar": {
          "iana_id": "801217",
          "registrar_name": "Endurance Digital Domain Technology LLP",
          "website_url": "https://publicdomainregistry.com/"
        },
        "registrant_contact": {
          "name": "REDACTED FOR PRIVACY",
          "company": "N/A",
          "street": "N/A",
          "city": "REDACTED FOR PRIVACY",
          "state": "Other",
          "zip_code": "REDACTED FOR PRIVACY",
          "country_name": "India",
          "country_code": "IN",
          "email_address": "please contact the registrar listed above",
          "phone": "REDACTED FOR PRIVACY",
          "fax": "REDACTED FOR PRIVACY",
          "mailing_address": "India"
        },
        "administrative_contact": {
          "name": "REDACTED FOR PRIVACY",
          "company": "REDACTED FOR PRIVACY",
          "street": "N/A",
          "city": "REDACTED FOR PRIVACY",
          "state": "REDACTED FOR PRIVACY",
          "zip_code": "REDACTED FOR PRIVACY",
          "country_name": "REDACTED FOR PRIVACY",
          "country_code": "N/A",
          "email_address": "please contact the registrar listed above",
          "phone": "REDACTED FOR PRIVACY",
          "fax": "REDACTED FOR PRIVACY",
          "mailing_address": "N/A"
        },
        "technical_contact": {
          "name": "REDACTED FOR PRIVACY",
          "company": "REDACTED FOR PRIVACY",
          "street": "N/A",
          "city": "REDACTED FOR PRIVACY",
          "state": "REDACTED FOR PRIVACY",
          "zip_code": "REDACTED FOR PRIVACY",
          "country_name": "REDACTED FOR PRIVACY",
          "country_code": "N/A",
          "email_address": "please contact the registrar listed above",
          "phone": "REDACTED FOR PRIVACY",
          "fax": "REDACTED FOR PRIVACY",
          "mailing_address": "N/A"
        },
        "billing_contact": {
          "name": "N/A",
          "company": "N/A",
          "street": "N/A",
          "city": "N/A",
          "state": "N/A",
          "zip_code": "N/A",
          "country_name": "N/A",
          "country_code": "N/A",
          "email_address": "N/A",
          "phone": "N/A",
          "fax": "N/A",
          "mailing_address": "N/A"
        },
        "name_servers": [
          "dns3.bigrock.in",
          "dns2.bigrock.in",
          "dns1.bigrock.in",
          "dns4.bigrock.in"
        ],
        "domain_status": [
          "clientTransferProhibited"
        ]
      }
    ]
  }
]

google

apple

stripe

apifreaks

1528+
TLDs
693M+
Active Domains
890M+
Domains Tracked
3692M+
WHOIS Records
5106M+
Host Names
14B+
DNS Records

Our Products

What is a Reverse Whois API?

Reverse Whois API

A forward WHOIS lookup starts with a domain and returns the owner. A reverse WHOIS lookup starts with an owner attribute - an email address, registrant name, company name, or domain keyword and returns all domains associated with it.

Reverse Whois API

Documentation

Features

What Reverse Whois API Provide

Seamlessly integrate valuable data and features into your platform.

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Email Based Lookup

Email-based lookup in reverse WHOIS search allows you to find all domains associated with a specific email address.

Company Based Lookup

Perform a reverse WHOIS search to find domain ownership details linked to a specific company for threat mitigation.

Registrant Based Lookup

Use WHOIS Reverse Search Lookup with WHOIS email search to retrieve ownership details for domain analysis.

Keyword Based Lookup

Use WHOIS Reverse Search Lookup with WHOIS email search to retrieve ownership details for domain analysis.

Use Cases

WHOIS in Action

See how our users leverage WHOIS data to gain actionable insights.

Data Enrichment

WhoisFreaks delivers reliable, up‑to‑date domain and website data to power CRM, marketing, and audience insights.

Domain Registration and Portfolio Analysis

Bulk WHOIS Lookup helps manage your domain portfolio, with Live and Historical WHOIS API.

Threat Intelligence

Our Reverse WHOIS service, powered by Live and Historical WHOIS API, helps uncover hidden data, and enhance threat.

Brand Monitoring & Brand Protection

Protect and monitor your brand and intellectual property with our real-time WHOIS API and Bulk WHOIS Lookup.

Competitive Intelligence

Bulk WHOIS Lookup reveals competitor domains information helping analyze portfolios and marketing strategies.

Research & Due Dilligence

WHOIS History Lookup supports domain or business due diligence by revealing ownership, history, and expiry details.

Integrate our WHOIS APIs now to power your threat intelligence, access real-time and historical domain data, and make smarter security decisions.

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FAQs

FAQs about the Domain WHOIS API: endpoints, parameters, response fields, and rate limits.

Can I perform a search on WHOIS records based on email address in reverse API?

Yes, you can search for WHOIS information using an email address. The email parameter allows you to retrieve domains associated with a specific email address. Please note that this search is limited to publicly available email addresses. The search is precise, so make sure to input the complete and exact email.

How do you perform a search using "company" parameter on WHOIS data in reverse API?

The company parameter enables you to search for domain WHOIS data based on a publicly available company name. Simply input the company name, and the API will return domains associated with that company using search based query. For example, if you enter "meta", the API will return all domains that are owned by companies with word "meta" in their names.

How do you perform a search using "owner" parameter on WHOIS data in reverse API?

With the owner parameter, you can search for domain WHOIS data based on the name of the domain owner that will be publicly available in records. Enter the owner's name, and the API will provide a list of domains linked to that owner using search based query. For example, if you enter "michael", the API will search that name in full name of the owner.

What is the "exact" match parameter in reverse WHOIS?

The "exact match" parameter is an optional feature in reverse WHOIS searches. When used with keywords, company names, or owner names, it ensures that the search results match the exact terms entered. This helps users find more precise and relevant information by filtering out results that don't perfectly align with the query.

Note: The "exact match" parameter can only be used with keywords, owner/registrant names, or company names. It is not applicable for email addresses, meaning you cannot use exact match to filter results based on email addresses.

How can I perform a regex-based search for email addresses in reverse WHOIS?

To search for email addresses using regex in reverse WHOIS, use the 'email' parameter with regex patterns. The 'email' parameter supports:

Exact match: Allows you to search for specific email addresses exactly as entered, such as [email protected] or [email protected]. This will return results that match these email addresses precisely.
Regex match: Enables more flexible searches using patterns to match a range of email addresses. For example, g***@outlook.com can match addresses like [email protected], and q*.l*@gmail.com can match addresses such as [email protected] or [email protected]. This approach accommodates variations within the specified pattern.

Note: Regex matching is only available for email addresses. For keywords, owner/registrant names, or company names, use the optional parameter exact set to 'false', or omit it as it defaults to 'false'.

What are the length limitations for the keyword parameter in reverse WHOIS API queries?

When using the keyword parameter in reverse WHOIS API queries, the keyword should be a minimum of 3 letters and a maximum of 63 letters.

Is the search case-insensitive?

Yes, all searches conducted through the reverse WHOIS api are case-insensitive. This ensures that your queries are not affected by the letter case of your input.

Can I combine multiple parameters in a single request in reverse WHOIS api?

Currently, the reverse WHOIS api supports using only one parameter per query. If you want to perform a more specific query, you can refine your query by using the appropriate parameter that best matches your criteria.

Do you offer pagination for the reverse WHOIS API, and how many records are provided per page?

Yes, we offer pagination for the reverse WHOIS API. Currently, we provide two modes for the reverse WHOIS api: the default mode and the mini mode. In the default mode, we provide 50 records per page, allowing you to retrieve a comprehensive list of domain WHOIS data. In the mini mode, we offer 100 records per page, which is ideal for users who prefer a more concise display of data. We provide only domain name, creation date, expiry date, update date , owner's name, company and email in mini mode.