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.
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To restrict the number of selection of checkboxes a user can select, you need to set the Minimum and Maximum Selections setup. To setup the Minimum and Maximum Selections of checkbox, just follow the instructions below.
However, I checked your form and I suggest that you use radio button field instead of checkboxes. By default radio button only allows one option to be selected.
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