How FreePDF works
FreePDF started with a simple idea: basic PDF tools should be free, private and unlimited. To make that possible we replaced the traditional model, where every file is uploaded to an expensive server, with one where your own device does the work.
Processing on your device
When you open a tool, your browser downloads the code it needs (only once, then it is cached). That code runs in Web Workers and WebAssembly, using your processor’s cores. OCR, for example, spreads pages across several cores at once.
- Privacy: your files never travel over the internet.
- Speed: no uploads and no queues.
- No limits: since we don’t pay servers per file, we don’t need to limit you.
Fair, proportional advertising
While your file is processed, we show an ad. Its length depends on the actual job: file size, number of pages and tool complexity.
| Job | Example | Ad |
|---|---|---|
| Light | Merge 2 small PDFs, rotate pages | 5 s |
| Medium | Number the pages of a long thesis | 10 s |
| Heavy | Compress a large scanned document | 20 s |
| Very heavy | OCR of a long document | 30 s |
Processing happens at the same time as the ad, so in most cases your file is ready when it ends.
Technology
FreePDF uses open-source technology: PDF.js (Mozilla) to render pages, pdf-lib to edit PDFs, Tesseract for OCR, docx to generate Word documents and Astro to serve ultra-fast static pages.