Open-source software used by these tools
These tools are mostly a careful assembly of open-source work done by other people. Here is what runs in your browser, and under which licence.
| Software | Licence | Used for |
|---|---|---|
| pdf-lib | MIT | Writing and editing PDF files |
| pdf.js (pdfjs-dist) | Apache-2.0 | Rendering PDF pages and extracting text |
| libheif (libheif-js) | LGPL-3.0 | Decoding HEIC/HEIF photos |
| jSquash codecs | Apache-2.0 | JPEG, PNG, WebP and AVIF encoding (MozJPEG, libwebp, libavif, OxiPNG) |
| FFmpeg (ffmpeg.wasm) | GPL-2.0-or-later | Video and audio conversion |
| Tesseract (tesseract.js) | Apache-2.0 | Optical character recognition |
| OpenCV (@techstark/opencv-js) | Apache-2.0 | Document edge detection in the camera scanner |
| ONNX Runtime Web | MIT | Running the background-removal models |
| U-2-Netp | Apache-2.0 | Background removal — fast model |
| MODNet | Apache-2.0 | Background removal — portrait model |
| ISNet general use | MIT | Background removal — high-quality model |
| SheetJS (xlsx) | Apache-2.0 | Reading and writing Excel files |
| Mammoth | BSD-2-Clause | Converting DOCX to HTML |
| Marked | MIT | Markdown to HTML |
| Turndown | MIT | HTML to Markdown |
| Prettier | MIT | Formatting JSON, HTML, CSS, JavaScript, Markdown and YAML |
| sql-formatter | MIT | Formatting SQL |
| js-yaml | MIT | YAML parsing |
| PapaParse | MIT | CSV parsing |
| jsdiff | BSD-3-Clause | Text comparison |
| pixelmatch | ISC | Visual comparison of rendered pages |
| QRCode | MIT | QR code generation |
| JsBarcode | MIT | CODE128, EAN-13/JAN and ITF barcodes |
| JSZip | MIT | Building ZIP downloads |
| exifr | MIT | Reading EXIF, IPTC and XMP metadata |
| c2pa-web | MIT | Verifying C2PA Content Credentials |
| SortableJS | MIT | Drag-and-drop reordering |
| Vite + vite-plugin-pwa (Workbox) | MIT | Build tooling and the offline service worker |
LGPL notice (libheif)
HEIC/HEIF decoding uses libheif, licensed under the LGPL v3. It is served as a separate, unmodified WebAssembly file that is not linked into our own code, so you are free to replace it with your own build of the same library. The source is available at the link above.
GPL notice (FFmpeg)
The video and audio tools load ffmpeg.wasm from a public CDN (jsDelivr) at the moment you use them. That build of FFmpeg is licensed under the GPL v2 or later; its sources are published by the FFmpeg project and by the ffmpeg.wasm project at the link above.
Models
Machine-learning models are downloaded from Hugging Face when a tool that needs them is used, and cached by your browser afterwards. We deliberately use only models with a permissive licence — no “non-commercial” weights, and nothing that would place a copyleft obligation on the people using these pages.