PDF.js is a web-based PDF viewer built with HTML5 and JavaScript that parses and renders PDF documents in the browser using web standards.
The project addresses the need to display PDF files natively in web applications without requiring plugins or server-side processing. It works by parsing PDF documents and rendering them using HTML5 canvas and other browser APIs. The tool provides both a standalone viewer component and a library that developers can integrate into their own applications. It includes features like text extraction, document navigation, and a PDF debugger for inspecting document structure.
Developers should choose PDF.js if they need to embed PDF viewing capabilities directly in web applications or build custom PDF readers. It suits projects requiring cross-browser compatibility, including support for older browsers through a legacy build. The tool is particularly valuable for applications that want to avoid server-side PDF processing or external dependencies. The project is built into Firefox version 19 and later, and an official extension is available for Chrome, demonstrating its maturity and broad adoption.
The project maintains a substantial base of real-world adopters, as evidenced by the fact that almost all open issues are raised by outside users rather than the core team. Maintainers typically respond to new issues and pull requests within hours. Work in the issue tracker is dominated by labels covering the viewer, core functionality, and information requests, reflecting the project's focus on the main rendering engine and user-facing components.
