> ## Knowledge Base Index
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> Use this file to discover available pages before exploring further.
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# Add mask to form (character limit in form)

### To limit the number of characters or add the ability to add only certain characters, you should add a mask.
# To set a mask, go to the settings of a specific field of your form:

![](https://storage.crisp.chat/users/helpdesk/website/7e782a40c0560c00/screenshot9_17je45.png)
# For example, if you want to be able to enter only numbers in the phone number field (limit on the number and type of symbol), then you should specify a mask:

`+{0[00]} 000 000[0000] [0000]`



![](https://storage.crisp.chat/users/helpdesk/website/7e782a40c0560c00/screenshot10_p6p88e.png)