How to use Fill PDF Form
- Add one fillable PDF that uses standard form fields.
- Read the field list the page draws from that file.
- Type a value for each field, or paste a JSON object of field names and values.
- Select Fill form and download the -filled.pdf copy.
Example: Fill PDF Form
Fill a small contact form that asks for a name and a confirmation check box.
Options
- Field values (JSON)
- One object that maps each field name to a string, number or true/false. A key you leave out keeps the value already stored in the form.
- Refresh the visible field text
- Rebuilds the field appearance with a standard PDF font. Leave it on unless the form already draws its own appearance and the rebuilt one looks wrong.
Supported inputs and limits
Where your input is processed
This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.
What makes a PDF fillable
A fillable PDF stores each field as a named object in a structure called an AcroForm, and a reader draws a small editable box on the page for it. Because the field has a name, this tool can list it and write a value that other readers understand. A scanned page or a printed-then-photographed form has no such objects, so the only way to make it fillable is to rebuild the form.
Questions about Fill PDF Form
Can I fill a scanned PDF?
No. A scan is a picture with no form fields underneath. Run text recognition and rebuild the form in a PDF editor, then fill that file here.
Why was my XFA form refused?
An XFA form keeps its fields in an XML layer that this engine cannot change safely. Open the file in the app that made it, export a standard AcroForm copy, and fill that instead.
Why did one field stay empty?
Only the names you supply are written. Check the field list on the page for the exact spelling, and leave a name out when the form should keep its stored value.
How do the field list and the JSON box work together?
Pick a file and the page lists every field already opened on its stored value. Editing one field merges just that value into the JSON box, and a field you leave alone is not written, so a stored answer or check mark survives. You can also type the JSON yourself and leave the field list alone.
How do I clear a field that already holds text?
Empty the field's box in the list. An empty string is written as an explicit clear, and the value in the JSON box becomes "". Leaving a field untouched is different: it keeps whatever the PDF already stores.