Is Fill PDF Forms free to use?

Yes. Every core tool, including Fill PDF Forms, is free to use with generous limits.

Are my files private?

Your document is processed entirely in your browser. It never leaves your device and is never uploaded to a server.

Why does it say my PDF has no fillable fields?

Only PDFs with real (AcroForm) form fields can be filled here. Many forms are flat — the boxes are just printed graphics. For those, use Sign PDF to place text or a signature on top of the page instead.

Which field types are supported?

Text boxes (including multiline), checkboxes, radio buttons, dropdowns, and multi-select option lists. Signature and button fields are listed but can't be filled — signing is a separate tool.

What does Flatten do?

Flatten merges your answers into the page content so the fields can no longer be edited. Leave it off if the form should stay editable in PDF viewers.

Why were some characters replaced in my answers?

Field appearances are drawn with the PDF standard font (Helvetica), which only covers Western/Latin characters. Characters outside that set — for example CJK or unmapped symbols — are swapped for the closest match, and the tool tells you how many were changed.

Edit

Fill PDF Forms

Detect the fillable fields in a PDF form, type your answers, and download the filled document — optionally flattened so it can't be edited.

100% free
Private — in your browser
No sign-up

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How to fill pdf forms

1
Upload a PDF that contains form fields.
2
Fill in the detected fields — text, checkboxes, radio buttons, dropdowns, and option lists — grouped by page.
3
Optionally turn on Flatten to make the filled fields permanent and uneditable.
4
Apply and download your filled PDF.

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