How can I add graph (pie) on thankyou page using calculations?

Hi, 

I wanted to show a graph (pie graph) on thankyou page, there are 4 hidden text fields, that takes values as average of various other fields. I want to show pie graph for these four values (calculated for these for hidden fields). 

How can i do this?

Unfortunately, it is not possible to show a graph using your form's  Thank you page.

However you may redirect the Thank you page to a custom page with your graph.

-How-to-Post-Submission-Data-to-Thank-You-Page

It means that you will need a custom script to process the form post data and create the charts.

We do have several other visual charts and reports that can be created from form data:
https://www.jotform.com/help/187-How-to-Create-a-Visual-Report-with-Your-Form-Submissions

Hope this information helps.