Is it possible to use formula in custom fields while submitting an issue?

[godson miller]

I am doing a form with custom fields in jira which is a IT Service request type issue. I wanted to display the estimated cost as a label or message pop up based on the values entered in the custom fields. 

[Mesut Yilmazyildirim]

You need to write or find a plugin to do that.

We are using Jira Misc Custom Fields