How to limit the selection of a checkbox?

Hi there. 

I'm building a form in which I wish to limit one choises into a certain amount of choices (lets say 3)

Afterwards, I want that the other choises will be grayed and not available... 

Is your system capable of doing that? 

Thanks

Do you mean to enable the user to select one of the checkboxes on your JotForm in a question?

If so, you may set the limit by enabling Entry limits in the Checkbox field properties.

When the user has selected more than one option for the limited check box, an error message will be displayed as shown below:

If you need to gray out the other options after selecting one, it may be required to use the source code of the form and write a custom code.

Hope this information helps! Let us know if you are referring something different. We will be happy to assist.