pdfcosmos

Credits & licenses

pdfcosmos is built entirely on open-source software. The engines that process your files run in your browser and never upload your documents to a server, and these projects are what make that possible. We keep this list current as we add new tools.

Engines that process your files

Everything in this group runs locally in your browser. None of these libraries uploads your documents to a server.

  • qpdf Apache-2.0

    The engine behind structural PDF operations (merging, splitting, and rotating).

  • @jspawn/qpdf-wasm Apache-2.0

    The WebAssembly build of qpdf that lets it run locally in your browser.

  • pdf.js Apache-2.0

    Renders the first-page thumbnail previews of your files.

  • pdf-lib MIT

    Creates new PDFs in your browser, used by Image to PDF to assemble your images into pages.

  • @pdf-lib/fontkit MIT

    Lets pdf-lib embed and subset a custom font, so the text tools can render Cyrillic, Greek, and other non-Latin characters.

  • Noto Sans OFL-1.1

    The bundled Unicode font. It is embedded (subsetted) when a tool places text (page numbers, Bates, header/footer, watermark, fill & sign) that falls outside the standard Latin-1 fonts.

  • fflate MIT

    Bundles multi-file results (e.g. split or rotated PDFs) into a single ZIP download, in your browser.

  • libheif (libheif-js) LGPL-3.0

    Decodes Apple HEIC/HEIF photos in your browser so HEIC to PDF works in every browser.

  • docx-preview Apache-2.0

    Renders Word .docx/.docm documents in your browser, powering Word to PDF.

  • html2canvas MIT

    Captures the rendered Word document, Excel sheet, or Markdown to an image so it can be placed into the PDF, in your browser.

  • marked MIT

    Renders Markdown to HTML in your browser, powering Markdown to PDF.

  • js-yaml MIT

    Parses and validates YAML in your browser, powering YAML to PDF.

  • UTIF.js MIT

    Decodes TIFF images (including multi-page) in your browser, powering TIFF to PDF.

  • postal-mime MIT

    Parses .eml email (MIME) messages in your browser, powering EML to PDF.

  • gifenc MIT

    Encodes GIF images in your browser (palette quantization), powering PDF to GIF.

  • @jsquash/avif Apache-2.0

    A WebAssembly AV1 image encoder that creates AVIF images in your browser, powering PDF to AVIF.

  • SheetJS (xlsx) Apache-2.0

    Reads and writes spreadsheets (.xls/.xlsx/.csv/.ods) in your browser, powering the Excel/CSV conversion tools (Excel to PDF, CSV to PDF, PDF to Excel, PDF to CSV).

  • Tesseract.js Apache-2.0

    A WebAssembly build of the Tesseract OCR engine, self-hosted and run entirely in your browser to power OCR PDF (making scanned PDFs searchable).

  • Tesseract OCR trained data (eng, spa, deu, fra, hin) Apache-2.0

    The bundled language models OCR PDF uses to recognise text (English, Spanish, German, French, Hindi), served from this site, not a third party.

How the site is built

The framework and styling behind these fast, static pages.

  • Astro MIT

    The framework that builds these fast, static pages.

  • Tailwind CSS MIT

    Styling and the site's design tokens.

  • Space Grotesk OFL-1.1

    The typeface used for headings. Self-hosted, never loaded from a font CDN.

Each project is distributed under its own license, linked above. We're grateful to their authors and contributors.