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.
You can set the field as "required" so that the user cannot submit the form without completing it.
1. Just select the field and click the Required button on the top
2. You can also click the properties icon of the field and choose Required.
If the user did not fill up the fields, a pop-up message will appear.
We also have a widget called Email Validator. This will make sure that a valid email is used on your form through a pass-code verification process.