PDFfriendly

PDFfriendly is an open-source software toolkit for creating, editing, and optimizing PDF documents. It aims to deliver standards-compliant output, robust accessibility, and efficient processing, offering libraries and command-line tools to generate PDFs from various sources, as well as to modify existing documents. The project emphasizes interoperability, reproducibility, and ease of integration into automated workflows.

Launched in 2013 by a collective of open-source developers and digital preservation specialists, PDFfriendly is maintained as a community project. It is released under the MIT License and hosted on a public repository, inviting contributions from individuals and institutions. The project has grown through collaboration with libraries, publishers, and researchers who rely on its extensible design and transparent development process.

Key features include support for tagged PDFs and PDF/UA accessibility, PDF/A archival compliance, page-level manipulation (merge, split, rotate, reorder), text extraction, font embedding and subsetting, image compression and optimization, metadata handling, and support for forms and annotations. It provides bindings for Java, Python, and JavaScript in addition to a cross-language command-line interface, enabling integration into diverse environments.

The core engine is written in C++ with language bindings to enable integration into larger workflows. It uses a modular architecture that can be extended with plugins and integrates with other open-source tools for rendering, validation, and encryption. It supports linearized PDFs for faster web viewing and incremental updates to large documents.

PDFfriendly is used by libraries, publishers, academic projects, and data preservation initiatives to automate PDF generation and processing tasks. Documentation, tutorials, and example pipelines accompany the project, and a growing community contributes code, tests, and translations.