Making requests | Documentation | Reverse MX API | WhoisXML API

Making requests

API endpoint

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Postman collection

Postman is a desktop and web application that allows you to make requests to an API from a graphical user interface. We recommend using Postman with WhoisXML APIs endpoints when exploring the APIs functionality, as well as when you are troubleshooting issues with your application.

The WhoisXML API Postman collection is available at the following links:

The collection includes a preconfigured environment. You will need to set up the api_key variable to fire each request. Get your personal API KEY on the My products page. If you have questions related to the API, contact us.

Input parameters


Required. Get your personal API KEY on the My products page.


Required. Mail server.


Optional. The domain name which is used as an offset for the results returned.

Since every response is limited to 300 records, you can retrieve the next page by putting the last domain name from the response into this parameter. For example, if the last domain name in the response is and the field "size" in the output equals 300, in order to retrieve the next page, call

If the parameter is omitted, you get arbitrary 300 records.

To get the first page, put 1 into the parameter.


Optional. Response output format.

Acceptable values: JSON | XML

Default: JSON

Free access

After Sign Up you automatically get a free subscription plan limited to 500 DRS credits.

Usage limits and 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.

This API is also available with a dedicated load balancer and premium endpoint to enable faster querying as part of our Premium API Services and Enterprise API Packages.