> For the complete documentation index, see [llms.txt](https://docs.keyfax.biz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.keyfax.biz/product-suite/admin/entities/databoxes/testing-databoxes-and-expressions.md).

# Testing Databoxes & Expressions

Expressions can be created against all types of Databox except Company Data (aka Fixed Text).

Wherever you create Expressions, a Test facility is provided. In essence, it will allow you to evaluate what happens when certain data is encountered by the Databox.

When you click **Test** (in the Editing pane, not the main menu) a popup window will appear where you can supply a value for the Databox by entering a value. Then click **Evaluate**. 

Any errors will be reported but, if all is well, you will see the results of the Expressions:

<div align="center"><figure><img src="/files/oLS0q6wK2jc2uK3gOAUV" alt=""><figcaption><p>Testing your Expressions</p></figcaption></figure></div>

### Here's an idea...

You might find that it's a useful idea to have a 'scratch' Databox whose only purpose is to house a number of example Expressions which you can use to test and confirm that the (sometimes esoteric!) formatting is correct. Here's such a random selection:

<div align="center"><figure><img src="/files/cZE6RRXbSAHctnG1Pi1d" alt=""><figcaption><p>Example Expressions</p></figcaption></figure></div>