> For the complete documentation index, see [llms.txt](https://domainmappingsystem.gitbook.io/domainmappingsystem-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://domainmappingsystem.gitbook.io/domainmappingsystem-docs/features/query-string-parameters.md).

# Query String Parameters

Domain Mapping System supports query string parameters in your URLs. Here's what you need to know to use query string parameters.

{% hint style="success" %}
Query string parameters are supported by default in the free version of Domain Mapping System.
{% endhint %}

Query string parameters have a wide variety of use-cases and formats, such as this example:

```
https://your-mapped-domain.com/?[trackingparam]=[value]&...
```

You might use query string parameters for any of the following use-cases and many others:

* Google UTM parameters
* Affiliate plugins
* Prefilling form field data on a page

Query string parameters should not be confused with subdirectories or pages of your site, like this:

```
https://your-mapped-domain.com/landing-page/
```

{% hint style="warning" %}
You should see the data "pass-through" your mapped domain, so data will be tracked in your corresponding platform for the primary site domain. For instance, if you're using Google UTM parameters, you'll see the UTM tracking data in the Google Analytics Dashboard for your **primary domain** and not the **mapped domain.**
{% endhint %}

In the future, we hope to add support for query string parameters to mapped domains independently of the primary domain. If you need this feature, please [submit a ticket](https://domainmappingsystem.com/support/).