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 am not sure if I have understood your question correctly.
Do you mean to ensure that the input value of a form field is actually a date? In that case you should go ahead and add "DateTime" field in your form which in under "Quick Tools". Please check the screenshot below:
Hope this helps.
Do get back to us if you meant to ask something else.