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PDF Forms

Fill PDF form fields online

Click to upload a PDF with form fields

About PDF Forms

PDF Forms reads the existing fillable fields from a PDF you upload and lets you type a value into each one, entirely in your browser using the pdf-lib library — your file is never uploaded to a server. It only fills in an existing form; it doesn't let you create a new form or add fields, checkboxes, radio buttons, or dropdowns to a PDF that doesn't already have them.

How to use PDF Forms

  1. 1Click the upload area and select a PDF that already contains fillable form fields.
  2. 2Type a value into each detected field.
  3. 3Click 'Fill and Download PDF' to write in your values and flatten the form.
  4. 4The filled, flattened PDF downloads automatically.

Frequently Asked Questions

Is PDF Forms free to use?

Yes, it's completely free with no signup required.

Can I create a new PDF form or add fields?

No — this tool only fills in fields that already exist in the PDF you upload. It doesn't let you add text boxes, checkboxes, or other fields.

What happens to checkboxes, radio buttons, or dropdowns in the form?

Their names are detected, but this tool only writes values into text fields, so other field types won't be filled in from this page.

Does it work with a PDF that has no form fields?

No — if the PDF has no fillable fields, you'll see "No form fields found in this PDF."

Tips & Tricks

  • After filling, the form is flattened, so your values become part of the page content and can't be edited again as form fields.
  • Only PDFs with an existing fillable form (an AcroForm) will show anything to fill in.
  • If a field doesn't appear editable, it's likely a checkbox, radio button, or dropdown rather than a text field.
  • Keep the original PDF if you might need to fill it again with different values, since flattening can't be undone.