# Must be Certain Format

This rule allows you to build a very specific format that you would like the value in your field to match.

{% hint style="success" %}
You can as many of these rules as you like and it will check against any one of them.
{% endhint %}

The rule utilises what is called a variable character which you can make up yourself. The variable character represents the space in the word where you can fill in any data you want. The remaining part of the value in your field must be identical to same part of the word set out in the format required.\
\
For example, we need all values in the field to follow the format: \
VALUE123 where 123 can be always different, e.g. VALUE124, VALUE939, VALUEPPP\
\
In this example, you choose a variable character that will not be in the word VALUE, for example an & symbol. The format required is then set as VALUE&&&.

![](/files/-Ma4kAispYhRTGfBtdOJ)

### Rule Parameters

| Parameter          | Description                                                                                              |
| ------------------ | -------------------------------------------------------------------------------------------------------- |
| Variable Character | Can be any character which should not be in the format below it. (more information and an example above) |
| Format             | The format required where the variable character can be the part of the word that can change.            |


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