To adjust the width of your form, you must modify the settings page with the desired size. You can modify these settings by logging in to emailmeform.com > mousing over the form you want to edit the width for and clicking "Edit" > clicking the "Form Settings" tab > scrolling down to the “Form Width” settings > entering your value:
Values may be in pixel (i.e. - "650" means 650 pixels) or percentage (i.e. - "100%" means the full width of the entire form on the page). Also note that lower on the settings page is a Responsive Form setting; setting forms to be responsive may conflict with form width settings if the form is in a narrow block of a site.