JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
Another way is to create an HTML page where you can place your code there (assuming it is a script) then upload the HTML page on a hosting site, if you have a website page. In your form, you will use the website page link or the path of the HTML page in your "Thank You" setting. Here's a guide on how to redirect your user to a different confirmation page: https://www.jotform.com/help/38-Redirecting-Users-to-a-Different-Page
We also have a Google Analytics widget that allows you to track conversion and visits from your form. Let us know if you need more help on this.