filehugger.comOpen Source Licences
Last updated: 11 August 2026
filehugger.com runs its conversions in your browser, which means the open source engines that do the work are downloaded to your device and executed there. This page lists every third-party component we ship, what it is used for, and the licence it is published under, so that the attribution travels with the code.
What we ship to your browser
| Component | Used for | Licence |
|---|---|---|
| PDF.js (pdfjs-dist) | Reading PDFs: rendering pages, extracting text, annotations, metadata and attachments. | Apache License 2.0 — Mozilla Foundation |
| pdf-lib | Writing PDFs: merging, splitting, rotating, cropping, page numbers, watermarks, signatures. | MIT. The minified bundle we ship also contains Microsoft's tslib helpers, Apache License 2.0. |
| Tesseract.js and tesseract.js-core | Optical character recognition, plus the English training data used to recognise text in scans and images. | Apache License 2.0. Upstream Tesseract OCR is likewise Apache License 2.0. |
| qpdf, compiled to WebAssembly | PDF encryption and decryption, and structural checks. | Apache License 2.0 (qpdf version 11 and later). |
| heic2any | Decoding HEIC and HEIF photos from iPhones so they can be converted to other formats. | The wrapper is published as MIT. It statically bundles libheif, which upstream is published under the GNU Lesser General Public License v3.0 — see the note below. |
Note on heic2any and libheif
We inspected the copy of heic2any that we serve and confirmed that the libheif module is compiled into it. libheif is published upstream under the LGPL v3.0, while the heic2any wrapper itself carries an MIT notice. Because the bundled WebAssembly cannot practically be relinked by an end user, the MIT notice on the wrapper does not by itself settle the licensing position of the whole bundle, and this has been raised upstream.
We are not lawyers and this page is not a legal opinion. We publish it because attribution is the right thing to do regardless of how that question resolves: if you use the HEIC tools on filehugger.com, your browser is running libheif, and its authors deserve the credit. The full licence text is available from the libheif project linked above. We are evaluating a replacement HEIC decoder with a clearer licensing position; if you maintain one, we would like to hear about it.
Fonts and hosting
Page text is set in Inter, published under the SIL Open Font License 1.1. Every engine listed above is served from our own domain rather than a third-party CDN, so using the tools does not hand your IP address to another provider.
Our own code
The site's interface, conversion pipeline, file-intelligence engine and e-invoice reader are written by Brothers IT Yazılım Arge ve Bilişim Hizmetleri Tic. San. Ltd. Şti. and are not open source at this time. Published measurements, test methods and rule implementations are documented on the site so that results can be checked independently rather than taken on trust.
Corrections
If you believe a component is missing from this page, or that a licence is stated incorrectly, tell us at info@brothers.net.tr and we will correct it. Attribution errors are worth reporting even when they seem minor.