Why do my forms look the perfect size when created but...

Why do my forms look the perfect size when created but once the code is put on the website the form will not hold the width and height dimensions?

Forms will inherit just about anything running in the page.  If there is any styling in the page that would apply to the same elements, that styling would apply to the form.  To prevent this, you can your forms iFrame code to embed the form:

https://www.jotform.com/help/148-Getting-the-Form-iFrame-Code

That should allow for the form to look the same embedded to your page as it does when previewed.