Credits and open-source licences
robinpdf does not have a PDF engine of its own. Everything that reads, renders, writes, encrypts or recognises text in your documents is open-source software written by other people. What this site adds is putting those pieces together so they run entirely in your browser, without uploading anything. The credit for the engine is theirs.
| Project | Version | What it does here | Licence |
|---|---|---|---|
| PDF.js | 6.3.289 | Reads and renders PDF pages: previews, PDF to image, text extraction, compare, redact. | Apache-2.0 |
| pdf-lib | 1.17.1 | Writes PDFs: merge, split, rotate, crop, page numbers, watermark, forms, signatures, metadata. | MIT |
| qpdf | see qpdf-wasm | Encrypts and decrypts PDFs for the protect and unlock tools. | Apache-2.0 |
| qpdf-wasm | 0.3.0 | The WebAssembly build that lets qpdf run inside the browser. | ISC |
| Tesseract.js | 7.0.0 | Runs OCR in the browser for OCR PDF and scanned pages in PDF to Word. | Apache-2.0 |
| Tesseract OCR | see Tesseract.js | The OCR engine itself (compiled to WebAssembly as tesseract.js-core), and the trained models for the twelve languages of the site. | Apache-2.0 |
| docx | 9.7.1 | Builds the Word document in PDF to Word. | MIT |
| fflate | 0.8.3 | Packs multi-file results into a single ZIP download. | MIT |
| Forge | 1.4.0 | Opens .p12 and .pfx certificate files, including older exports, in Sign with Certificate. | BSD-3-Clause |
| PKI.js | 3.4.0 | Reads and checks the digital signatures in Verify PDF Signature, using the browser’s own cryptography. | BSD-3-Clause |
| ASN1.js | 3.0.10 | Decodes the certificate and signature data that PKI.js checks. | BSD-3-Clause |
| Inter | 5.3.0 | Body typeface, by Rasmus Andersson. Self-hosted, via Fontsource. | OFL-1.1 |
| Poppins | 5.3.0 | Heading typeface, by Indian Type Foundry. Self-hosted, via Fontsource. | OFL-1.1 |
| Astro | 7.3.2 | Builds the site into static pages. Runs at build time, not in your browser. | MIT |
Each licence text is in the project's repository, linked above. If you maintain one of these projects and something here is wrong or incomplete, write to [email protected] and it gets fixed.