PDF Form FillerFill out interactive PDF form fields in your browser.

PDF Form Filler
Fill out interactive PDF form fields in your browser.
Upload PDF Form
Drop a PDF with form fields.
Fill Fields
Enter values for detected text, checkbox, and dropdown fields.
Download
Save the filled PDF form.
What Is PDF Form Filler?
The PDF Form Filler automatically detects interactive form fields in your PDF and presents them for editing. Supports text fields, checkboxes, dropdowns, and radio groups. Simply upload your PDF form, fill in the values through an intuitive interface, and download the completed form. The tool preserves all original formatting and non-form content. Ideal for filling out government forms, applications, contracts, or any PDF with interactive fields. All processing stays in your browser — your sensitive form data never leaves your device.
Why Use Our PDF Form Filler?
- Auto-detects all form field types
- Supports text, checkbox, dropdown, and radio fields
- Preserves original document formatting
- Sensitive data stays in your browser
Common Use Cases
Government Forms
Fill out tax forms, applications, and permits.
Contracts
Complete contract fields digitally.
Applications
Fill job or school application forms.
Insurance
Complete claim forms and policy documents.
Technical Guide
Uses pdf-lib to load the PDF and access its AcroForm. Iterates through form fields using getForm().getFields(), extracting field names and types. Renders appropriate input controls for each field type (text input for PDFTextField, checkbox select for PDFCheckBox, text input for PDFDropdown and PDFRadioGroup). When filling, uses the corresponding pdf-lib methods: setText, check/uncheck, select. The filled PDF is saved preserving all original content.
Tips & Best Practices
- 1Form fields are auto-detected — no manual setup needed
- 2Leave fields empty to keep their original values
- 3Checkbox values are "true" or "false"
- 4For dropdowns, enter an exact option value
Related Tools
Frequently Asked Questions
QWhat field types are supported?
QWhat if no fields are found?
QCan I add new fields?
QDoes filling flatten the form?
QIs my data secure?
About PDF Form Filler
PDF Form Filler is a free online tool from FreeToolkit.ai. All processing happens directly in your browser — your data never leaves your device. No registration required. No ads. Just fast, reliable tools.













