How it works
The PDF Form Filler reads the AcroForm fields embedded in a PDF document — text fields, checkboxes, radio buttons, dropdowns — displays them as a form, lets you type values, and produces a flattened PDF with the values baked in as static content. The output is identical to what you'd get from opening the PDF in Acrobat, filling the form, and printing to PDF.
When to use this instead of Acrobat: you need to fill the same form repeatedly with data from a spreadsheet. You're on a device without Adobe Acrobat or a PDF plugin. You need a filled PDF that cannot be re-edited (a flattened PDF). You're working with a form that has JavaScript issues in browser PDF viewers.
How to use it: 1. Upload a PDF that contains AcroForm form fields. 2. The tool reads all field names and displays an input for each one. 3. Enter values. Checkbox fields accept "true" or "1" to check; "false" or "0" to leave unchecked. 4. Click Fill & Flatten Form. The completed, flattened PDF downloads.
AcroForm vs XFA forms: this tool supports AcroForm format (the standard used by most fillable PDFs). XFA forms (used by some Adobe LiveCycle documents, often found in government forms) are a different format and may not render field names correctly. If no fields appear after upload, the PDF may use XFA format.
After flattening: the output PDF is no longer interactive — fields appear as normal text and cannot be edited. This is intentional for distribution purposes. If you need to keep the fields interactive, open the PDF in a desktop PDF editor instead.
Privacy: all form field parsing and filling runs in the browser using pdf-lib. Your form data never leaves your device.
Frequently Asked Questions
- Upload the PDF — the tool will display a list of all detected AcroForm fields. If the list is empty and a 'No fillable fields found' message appears, the PDF either has no interactive fields (it may be a flat form that looks like a form but has no underlying field objects) or uses the XFA format (Adobe LiveCycle), which this tool does not support. Many government and institutional forms are XFA-based.
- The tool flattens the form as part of the download process — all field values are converted to static text embedded in the page content. The output PDF is no longer interactive: fields cannot be cleared, changed, or re-filled after download. This is intentional for documents meant for distribution. If you need to preserve the interactive fields, open the PDF in a desktop PDF editor instead.
- Some AcroForm fields have field types that require specific value formats — checkboxes expect 'true'/'false' or '1'/'0'. Other fields may be read-only or calculated fields that don't accept input. Fields with validation scripts (e.g., date format validation) cannot be enforced in this browser-based tool — enter values in the expected format for best results.
- The tool attempts to load the PDF with the ignoreEncryption flag, which works for PDFs with user passwords removed. Ownership-protected PDFs (where filling is restricted by the creator) may not allow modification. If the form fields fail to appear, the PDF likely has modification restrictions that prevent programmatic filling.