Standing on the shoulders of open source
Every tool on this site runs entirely in your browser — and that is only possible because brilliant people released their work as open source. This page credits every engine we ship, with its license and a link to the source.
A special note on FFmpeg: our video and audio tools use unmodified builds of FFmpeg compiled to WebAssembly by the ffmpeg.wasm project, licensed under GPL-2.0-or-later. The complete corresponding source code is available at the links below.
| Engine | License |
|---|---|
| FFmpeg / ffmpeg.wasm | GPL-2.0-or-later |
| PDF.js | Apache-2.0 |
| pdf-lib | MIT |
| pdf-inspector | MIT |
| qpdf | Apache-2.0 |
| Bergamot / Firefox Translations | MPL-2.0 |
| SheetJS CE | Apache-2.0 |
| docx | MIT |
| docx-preview | Apache-2.0 |
| foliate-js | MIT |
| @webtoon/psd | MIT |
| heic2any | MIT |
| jSquash (AVIF/WebP/JPEG/OxiPNG) | Apache-2.0 |
| browser-image-compression | MIT |
| VTracer | MIT |
| signature_pad | MIT |
| fflate | MIT |
| JSZip | MIT |
| Papa Parse | MIT |
| js-yaml | MIT |
| IBM Plex (fonts) | OFL-1.1 |
To every maintainer on this list: thank you. ♡