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.
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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 think you're referring to the demo form in the page for the Calorie Intake Calculator widget: https://widgets.jotform.com/widget/calorie_intake_calculator
Here is also the link to the demo form: http://form.jotformpro.com/form/52220713451948
You may add the widget to your form by following the steps on this guide: How-to-Add-a-Widget-to-your-Form
You can also clone the demo form by following this guide: How-to-Clone-an-Existing-Form-from-a-URL
Hope this helps.