Output format | Documentation v3 | Email Verification API | WhoisXML API
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WHOIS / WHOIS History
WHOIS / WHOIS History

Provide current and historical ownership information on domains / IPs. Identify all connections between domains, registrants, registrars, and DNS servers.

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DNS / DNS History

Look into all current and historical DNS / IP connections between domains and A, MX, NS, and other records. Monitor suspicious changes to DNS records.

IP Geolocation / IP Netblocks
IP Geolocation / IP Netblocks

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.

Domain Research Suite (DRS)
Domain Research Suite (DRS)

Access our web-based solution to dig into and monitor all domain events of interest.

Domain Research Suite (DRS)
Domain Research Suite (DRS)

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.

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WhoisXML API Predictive Threat Intelligence
Predictive Threat Intelligence

Detect and block access to and from dangerous domain names before malicious actors can weaponize them. Contact us today for more information.

WhoisXML API Internet Infrastructure
Internet Infrastructure

Unlock integrated intelligence on Internet properties and their ownership, infrastructure, and other attributes.

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Enterprise API Packages

Our complete set of domain, IP, and DNS intelligence available via API calls as an annual subscription with predictable pricing.

Security Intelligence (SI) Suite
Security Intelligence (SI) Suite

Offers complete access to WHOIS, IP, DNS, and subdomain data for product enrichment, threat hunting and more.

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API 2.0 documentation

Output format: API v3

{
    "username": "support",
    "domain": "whoisxmlapi.com",
    "emailAddress": "support@whoisxmlapi.com",
    "formatCheck": "true",
    "smtpCheck": "true",
    "dnsCheck": "true",
    "freeCheck": "false",
    "disposableCheck": "false",
    "catchAllCheck": "true",
    "mxRecords": [
        "aspmx.l.google.com"
    ],
    "audit": {
        "auditCreatedDate": "2023-10-17 06:24:50.012 UTC",
        "auditUpdatedDate": "2023-10-17 06:24:50.012 UTC"
    }
}

Output parameters

username
An username is the part of an email address that comes before the @ symbol.
domain
An email domain is the part of an email address that comes after the @ symbol. For personal emails, it is most often gmail.com, outlook.com or yahoo.com. However, in a business context, companies are almost certain to have their own email domain.
emailAddress
The email address to be verified.
formatCheck
Lets you know if there are any syntax errors in the email address. This is a basic check that’s done to catch any simple typos or major errors. This value will be 'true' if there are no errors, and 'false' otherwise. Behind the scenes, the API service is handling all these types of verification checks for you in a number of interesting ways.
smtpCheck
Checks if the email address exists and can receive emails by using SMTP connection and email-sending emulation techniques. This value will be 'true' if the email address exists and can receive email over SMTP, and 'false' if the email address does not exist on the target SMTP server or temporarily couldn't receive messages. The value will be null if the SMTP request could not be completed, mailbox verification is not supported on the target mailbox provider, or not applicable.
dnsCheck
Ensures that the domain in the email address, eg: gmail.com, is a valid domain. This value will be 'true' if the domain is good and 'false' otherwise. May be 'null' for invalid or non-existing emails.
freeCheck
Check to see if the email address is from a free email provider like Gmail or not. This value will be 'false' if the email address is not free, and 'true' otherwise. May be 'null' for invalid or non-existing emails.
disposableCheck
Tells you whether or not the email address is disposable (created via a service like Mailinator). This helps you check for abuse. This value will be 'false' if the email is not disposable, and 'true' otherwise. May be 'null' for invalid or non-existing emails.
catchAllCheck
Tells you whether or not this mail server has a “catch-all” address. This refers to a special type of address that can receive emails for any number of non-existent email addresses under a particular domain. Catch-all addresses are common in businesses where if you send an email to test@hi.com and another email to non-existent test2@hi.com, both of those emails will go into the same inbox. Possible values are 'true' or 'false'. May be 'null' for invalid or non-existing emails.
mxRecords
Mail servers list. May be absent for invalid or non-existing emails.
audit
Record update dates.