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.
By default, there's no time limit to fill a form.
If you want to set a limit on it there are a couple of ways to do it.
You can check this guide: http://www.jotform.com/help/137-How-to-Limit-Submissions-in-a-Form if you want to set a limit on your form based on a number of submissions or an expiration date.
There's also the countdown widget in case you want to set a time limit to complete the form.