**Pete**I have setup a number field to capture the number units required, and a unbit price in the product fields. How do I create a rule to multiply number by unit cost?

- JotForm Founder
**aytekin**You do not need to create a rule. If you used the quantity field on the product options, it will calculate the total by making the multiplication. You are using one of the payment fields under Payment Tools, is that right? Can you post the URL of the form?