Open-source licenses
This site is built on open-source software. Thank you to everyone who maintains it.
Command-line engines on the server (Ghostscript, Poppler, Pandoc and others) are run as separate, unmodified programs and are not linked into our code. Source code for them is available from the links below.
| Component | Authors | License |
|---|---|---|
| pdf.js | Mozilla | Apache-2.0 |
| pdf-lib | Andrew Dillon | MIT |
| Next.js / React | Vercel / Meta | MIT |
| Tailwind CSS | Tailwind Labs | MIT |
| Lucide icons | Lucide contributors | ISC |
| dnd kit | Claudéric Demers | MIT |
| JSZip | Stuart Knightley | MIT (dual MIT/GPLv3) |
| heic2any (bundles libheif) | Alex Corvi / libheif authors | MIT / LGPL-3.0 |
| UTIF.js / UPNG.js | Photopea | MIT |
| node-qrcode | Ryan Day | MIT |
| jsdiff | Kevin Decker | BSD-3-Clause |
| Inter, Dancing Script, Great Vibes, Caveat, Homemade Apple | Various | SIL OFL 1.1 / Apache-2.0 |
| DejaVu Sans | DejaVu fonts team | Bitstream Vera / public domain |
| Fastify | Fastify team | MIT |
| BullMQ / ioredis | Taskforce.sh / ioredis contributors | MIT |
| zod | Colin McDonnell | MIT |
| Playwright (Chromium) | Microsoft / Chromium authors | Apache-2.0 / BSD-3-Clause |
| qpdf | Jay Berkenbilt | Apache-2.0 |
| Ghostscript | Artifex Software | AGPL-3.0 (run as an unmodified separate program) |
| Poppler | Poppler developers | GPL-2.0-or-later (run as separate programs) |
| LibreOffice | The Document Foundation | MPL-2.0 |
| Tesseract OCR | Tesseract contributors | Apache-2.0 |
| OCRmyPDF | James R. Barlow | MPL-2.0 |
| Pandoc | John MacFarlane | GPL-2.0-or-later (run as a separate program) |
| pikepdf | James R. Barlow | MPL-2.0 |
| pdfplumber | Jeremy Singer-Vine | MIT |
| openpyxl | openpyxl team | MIT |
| python-pptx | Steve Canny | MIT |
| PyMuPDF / MuPDF | Artifex Software | AGPL-3.0 (run in a separate helper process) |
| fontTools | fontTools authors | MIT |
| Liberation fonts / DejaVu fonts | Red Hat / DejaVu authors | SIL OFL 1.1 / Bitstream Vera licence |