What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
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.
Are you referring to the form width when you are in the form builder? Or is it when you embed the form in your website? I don't see any problems in the form in terms of its width so maybe you are talking of a different thing. How about sending us a screenshot here?
Check this guide for adding a screenshot to this support forum: http://www.jotform.com/answers/277033.