Domain Availability API User Guide

Domain Availability API helps you check whether a domain name is available for registration quickly and accurately.

WhoisXmlApi.com provides RESTful APIs. It is designed for server-to-server communication between your system and the WhoisXmlApi.com network using standard HTTP or HTTPS protocols. Query responses are delivered in either XML or JSON format based on your requests which are made via GET/POST methods.

To get started you need a developer's account with WhoisXmlApi.com. Authentication is required each time in order to use the API. The first 500 domain name availability lookups are complimentary when you register for a free developer account.

API status

You can check the API's current performance and availability status on the API Status Page.

Making a Call to Domain Availability API Web Service

Use the following URL:

https://www.whoisxmlapi.com/whoisserver/WhoisService?cmd=GET_DN_AVAILABILITY&domainName=test.com&username=xxxxx&password=xxxxx&getMode=DNS_AND_WHOIS

Supported input parameters

Parameters	Values
domainName	required, the domain for which domain info is required
username	required unless ApiKey authentication is used, your account username
password	required unless ApiKey authentication is used, your account password; *make sure it is URL-encoded if it contains special characters (&, %, etc.)**
requestObject	required unless password authentication is used, encoded user identifier for ApiKey authentication
digest	required unless password authentication is used, ApiKey access token
cmd	required, GET_DN_AVAILABILITY
outputFormat	XML \| JSON (defaults to XML)
getMode	DNS_AND_WHOIS \| DNS_ONLY (defaults to DNS_ONLY) the default mode is the fastest, the DNS_AND_WHOIS mode is slower but more accurate

Authentication

Password authentication

This method uses your account's username and password to authenticate with the web service. Just pass your credentials as query string parameters (username, password).

API key authentication

Generate access tokens providing your API and secret keys to make Domain Availability API calls without sending your username and password. These tokens will need to be included as part of the request URL (requestObject, digest). Please, note that all tokens expire after 5 minutes and will have to be regenerated. Access the API Key Management section of your account to create your keys (make sure the key you're using is marked as active).

TLDs Supported

We support thousands of TLDs, both gTLDs and ccTLDS. You can see the entire list here.

Sample Output

XML (UNAVAILABLE)

XML (AVAILABLE)

JSON (UNAVAILABLE)

JSON (AVAILABLE)

Output Schema

Usage Limits & Requests Throttling

The maximum number of requests per second is 30. In case that the limit is breached, your subsequent requests will be rejected until the next second.

Sample Output

XML

JSON

Query Account Balance Information

In order to query your account balance, use the following URL:

https://www.whoisxmlapi.com/accountServices.php?servicetype=accountbalance&username=xxxxx&password=xxxxx

Supported input parameters

Parameters	Values
servicetype	required, type of service; in this case, "accountBalance"
username	required, your account username
password	required, your account password; *make sure it is URL-encoded if it contains special characters (&, %, etc.)**
output_format	XML \| JSON (defaults to XML)

You will receive a response with your account balance.

Account Balance Low or Zero Notification

When your account balance falls below certain level (default is 100, but customizable as per your need) you will receive an email alert. Another email will be sent when your account balance reaches 0.

To customize the warning level, use the URL:

https://www.whoisxmlapi.com/accountServices.php?servicetype=accountUpdate&username=xxxxx&password=xxxxx&warn_threshold=30

Supported input parameters

Parameters	Values
servicetype	required, type of service; in this case, "accountUpdate"
username	required, your account username
password	required, your account password; *make sure it is URL-encoded if it contains special characters (&, %, etc.)**
warn_threshold	a positive number (defaults to 10) when your account balance reaches this value a warning email will be sent
warn_threshold_enabled	0 \| 1 (defaults to 1) indicates whether the low balance warning notification should be sent at all
warn_empty_enabled	0 \| 1 (defaults to 1) indicates whether the zero balance email notification should be sent to you
output_format	XML \| JSON (defaults to XML)

Usage of HTTP & HTTPS

You can use both http and https to make API queries. With HTTPS the connection will be more secure but slightly slower.

XML Schema/ Domain Availability Query Result Documentation

You can download the following for your reference:

xml schema

sample xml result

Sample code for making a query to Domain Availability API Web Service

You may view examples of querying Domain Availability API by clicking on the following links or visiting our GitHub page

User password authentication

C# code: example, full project

Java code: example, full project

Javascript code: example

NodeJS code: example

Perl code: example

PHP code: example

PowerShell code: example

Python code: example

Ruby code: example

API key authentication

C# code: example, full project

Java code: example, full project

Javascript code: example

NodeJS code: example

Perl code: example

PHP code: example

PowerShell code: example

Python code: example

Ruby code: example

Terms of Service or SLA for using Domain Availability API

Please click on the link below to review the

Printable guide

You can also download the PDF version of this guide.