How to Change the Font Size in a PDF Form Field. Portable Document Format, or PDF, documents allow users with different operating systems, fonts and programs to view a file.

LibreOffice Writer can create fillable PDFs from scratch with built-in tools. Start by opening a blank document and adding form fields using the Form Controls and Form Design toolbars. To export as an ...

Adobe Acrobat has a free online PDF form filler tool that lets you fill out PDF form fields, add text boxes, checkmarks, circles and other symbols.

Editing Interactive Forms If a PDF form you open contains editable fields, a purple bar will appear in Reader or Acrobat. Check the box on this bar if you want to highlight all available fields.