Fill PDF Forms
Fill PDF form fields online
Click or drop a PDF with form fields hereChoose a PDF with form fields
About Fill PDF Forms
Fill PDF Forms opens a PDF that already contains fillable fields (an AcroForm) and shows every field with its current value: text boxes, checkboxes, radio groups, drop-down and multiple-choice lists. Only the fields you change are written back, so values already in the form stay as they were. Read-only fields, signatures, and push buttons are left alone unless you flatten the form, which turns every field into page content. You can keep the form fillable or flatten it so the values become part of the page. It does not create new fields, and XFA forms made with Adobe LiveCycle cannot be filled here. pdf-lib reads and fills the fields inside your browser.
How to fill a PDF form online
- 1Choose a PDF that has fillable fields; each field appears with its name and current value.
- 2Type in text fields, select checkboxes, and pick radio or list options; fields you do not touch keep their values.
- 3Check "Flatten the form" if the values must no longer be editable.
- 4Click "Fill and download PDF" to build the file, then "Download" to save filled_form.pdf.
Formats and limits
- Input
- PDF with AcroForm fields
- Field types
- Text, checkbox, radio group, drop-down list, multiple-choice list
- Left unchanged
- Signature fields, push buttons, and read-only fields, unless you flatten the form
- Characters
- Western European letters with the form's standard font
- Result
- filled_form.pdf, still fillable or flattened
Where your file is processed
The form is read and filled in your browser with pdf-lib; the PDF and the values you type are not sent to our servers. A form that opens without a password but restricts editing, as many official forms do, is decrypted in the browser before filling.
Frequently asked questions
Can it fill a scan or a PDF whose boxes are only drawn?
No. Those have no AcroForm fields, so the page says no form fields were found. If the file is an XFA form made with Adobe LiveCycle or Designer, the page says so instead, since only Adobe Acrobat or Reader can fill those.
Will the values already in the form be kept?
Yes. Each field opens with its current value, and only the fields you change are written when you save. A field marked read-only by the form's author is shown but cannot be changed here.
Can I type Cyrillic, Greek, or Chinese into a field?
No, not with the standard PDF form font, which writes Western European letters only. In that case saving stops with a message explaining which character could not be written, instead of producing a broken file.
Should I flatten the form?
Yes, but only when the values must stay as they are. Flattening turns every field into part of the page, so nobody can edit it in a PDF reader, and it cannot be undone. Leave it unchecked to send a form the next person can still change.
Tips and tricks
- ✓To sign the completed form, open filled_form.pdf in Sign PDF after filling it.