Pandoc

Pandoc is a free, open-source document converter written in Haskell. It provides a universal intermediate representation that allows converting between a wide range of markup and word-processing formats. Created by John MacFarlane and maintained by a community of contributors, Pandoc is widely used in scholarly writing and content workflows.

Supported input formats include Markdown (Pandoc's extended version), reStructuredText, AsciiDoc, Textile, HTML, LaTeX, Word (.docx), OpenDocument (.odt), MediaWiki, OPML, and more. Output formats include HTML, LaTeX, PDF (via a LaTeX engine), Word (.docx), OpenDocument (.odt), RTF, EPUB, MOBI, as well as slide formats such as Beamer (PDF) and reveal.js HTML slides. It can also emit plain Markdown or other formats.

Pandoc's conversion process reads the source into an AST, then writes it in the target format. This architecture enables features such as custom templates, CSS for HTML output, and syntax highlighting. The system supports bibliographies and citations via CSL styles, with BibTeX, BibLaTeX, or CSL JSON sources.

Extensions and customization include filters (written in Haskell or Lua since newer versions support Lua filters), which transform the AST during conversion. Users can control document structure with templates, metadata blocks, and command-line options. Pandoc is cross-platform and available as a standalone binary; it can be installed via package managers or compiled from source.

Pandoc is released under the GNU General Public License and is actively maintained by its developers and community. It is widely used in academic and publishing workflows to convert documents for web, print, and e-book formats.