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.
I'm sure a lot are doing it. For multi-page forms, please follow this guide: http://www.jotform.com/help/119-How-to-Create-Multi-Page-Forms.
For calculation: http://www.jotform.com/help/259-How-to-perform-calculation-in-the-form.
For conditional logic: http://www.jotform.com/help/57-Smart-Forms-Using-Conditional-Logic.
If you could explain what form are you trying to create, we'll be happy to assist you about it. We can also create a sample form.
Also, try to check our form templates gallery: http://www.jotform.com/form-templates/