> For the complete documentation index, see [llms.txt](https://docs.verbdata.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verbdata.com/data-transformations/building-transformations/transformation-steps/map-values.md).

# Map Values

Enables changing values within a column with a specified Mapping formula or based on comparison criteria from a related table. If the expected values are not found, the Map Value transformation step can return;

* Original value 
* Null value 
* Blank/empty string 
* Write custom value

The results can either Override Input Column, or create a new Column.

When value replacement is a list of custom values, you can paste a 2 column tab delimited list from Excel (or similar) by clicking the Paste Multiple Values button.

Search is not case sensitive.

When performing a replacement on a text column from List of Custom Values, you can use `{blank}` to represent an empty string and `{null}` to represent a null value:

![](/files/u1HhnwGMyzf39zvamHGb)

{% hint style="info" %}
The percent sign % is the search wildcard to be used to match any characters before and after the string to search.

i.e. %verb% returns all values which include the word “verb” anywhere in the text string
{% endhint %}


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