How to Fill In a PDF Form Online for Free

Two Types of PDF Forms

Before choosing a tool, it helps to know what kind of form you have. Interactive forms have built-in fillable fields — click on them and type directly. Flat forms are static PDFs that look like forms visually but have no clickable fields — you need to place text boxes over the printed lines.

Filling an Interactive PDF Form

Interactive PDF forms work directly in any modern PDF viewer. In a browser, open the PDF in Chrome or Firefox — both have built-in PDF viewers that let you type into form fields, check boxes, and select radio buttons. Fill in your answers, then print to PDF or use "Save as PDF" to preserve the completed form.

Filling a Flat PDF Form

For flat forms (no clickable fields), you need a tool that lets you add text boxes over the page. Free online options include PDF Filler and Adobe's free Reader with commenting tools. Simply add a text annotation wherever you need to write, position it over the printed line, and adjust the font size to match.

Adding a Signature to a PDF Form

Once filled, many forms require a signature. Use the Sign PDF tool to draw, type, or upload your signature and place it in the signature box before downloading.

Saving Your Completed Form

After filling, always save as PDF (not just close the tab). In Chrome: click the print icon in the PDF viewer, choose "Save as PDF" as the destination, and save. This bakes your entries into the file so they survive being forwarded by email.