ALLYX ONE
100% browser-based · zero uploads

PDF Form Filler

Fill out PDF forms online for free — no account, no software, nothing to install. Upload your PDF, type in your answers, and download the completed form instantly. Your file stays on your device the entire time.

Drop your PDF here, or browse

PDF files up to 50 MB

How It Works

1

Upload your PDF

Drop your fillable PDF onto the page or click to browse. The tool reads the file directly in your browser and automatically detects every interactive form field.

2

Fill in your answers

Each field appears as the right input type — text box, checkbox, radio button, or dropdown. Type or select your answers, then optionally lock the form to prevent further edits.

3

Download the completed form

Click download and the completed PDF is saved directly to your device. Nothing is sent to a server — your form data stays completely private.

How to Fill a PDF Form Online

  1. Drop or select your PDF — click the upload area and choose your file, or drag and drop it directly onto the page.
  2. Review the detected fields — the tool lists every interactive field found in the document. Text boxes, checkboxes, radio buttons, and dropdowns are all supported.
  3. Type or select your answers — fill in each field as you would in Adobe Acrobat or any PDF viewer, right here in the browser.
  4. Choose whether to lock the form — tick "Lock form after filling" if you want the fields permanently embedded so the document cannot be edited further.
  5. Download — click the button and the completed PDF saves to your device automatically.

Features

  • Completely private — your PDF is processed locally using pdf-lib, an open-source library that runs entirely in your browser. No file data is ever transmitted.
  • All standard AcroForm field types — text (single-line and multi-line), checkboxes, radio button groups, dropdown lists, and option lists.
  • Optional form flattening — lock filled values permanently into the page so the document cannot be edited after download.
  • No account required — open the page and start filling immediately. No sign-up, no email, no watermarks.
  • Works on any device — desktop, laptop, tablet, or mobile. Any modern browser is supported.

Frequently Asked Questions

Is my PDF uploaded to your servers?

No. Your file never leaves your device. All processing — reading the form fields, saving your answers, and generating the filled PDF — happens locally in your browser using pdf-lib. Nothing is transmitted to any server.

What types of PDF form fields are supported?

All standard AcroForm field types are supported: text fields (single-line and multi-line), checkboxes, radio buttons, dropdown lists, and option lists. Push-button fields and XFA-based forms (used in some Adobe-created PDFs) are not currently supported.

Why does it say "No form fields detected"?

Some PDFs look like forms but are actually static pages with no interactive fields — for example, a scanned document or a form that was printed to PDF. This tool can only fill PDFs that contain AcroForm interactive fields. If your document has none, you would need to use a PDF editor to add fillable fields first.

What does "Lock form after filling" do?

This option flattens the form, permanently embedding your filled values into the PDF page content. The resulting PDF can no longer be edited in a form editor — the fields become part of the static page. Useful when sharing a finalized document that should not be changed.

Can I fill a password-protected PDF?

No. Encrypted PDFs cannot be read until unlocked. Use the PDF Unlock tool on this site to remove the password, then upload the unlocked file here.

Is this tool free?

Yes, completely free. No account required, no watermarks added to your PDF, and no hidden charges — ever.