Guides

How it works

Three steps, zero uploads. Here is exactly what happens when you use a tool.

1. Choose a tool

Select the tool you need from the collection — merge, split, compress, convert, secure, extract and more. Each tool has its own page with instructions and limitations.

2. Add your files

Select files from your device using the browser's file picker, or drag and drop them into the panel.

Your files never leave your device. The file is read by JavaScript in your browser and processed locally — there is no upload step and no server.

3. Get results

When processing finishes, download your file. Multi-file outputs arrive as a ZIP. That's it — no account, no email, no waiting.

The technical model

FreePDFToolbox is a static website. The processing code runs on your device:

  • PDF manipulation uses pdf-lib, compiled to JavaScript that runs in your browser.
  • Rendering, text extraction and image extraction use pdf.js — the same engine inside Firefox.
  • OCR uses Tesseract, compiled to WebAssembly, with the language model bundled locally.
  • Heavy work runs in the browser's worker threads where possible, with progress shown.

No request to any server ever contains your document.

Verify it yourself

Open your browser's developer tools (F12), go to the Network tab, then process a file. You will see requests for page assets — but none of them carry your file's data.

Limitations, honestly

Local processing means your device does the work. Very large files are slower, OCR depends on scan quality, and some advanced operations (certified redaction, certified PDF/A, certified digital signatures) are beyond what browser libraries can guarantee. Every tool documents its limits.