kkFileView is a document preview server that renders dozens of file formats for online viewing through a web interface.
The project solves the problem of displaying diverse document types in a browser without requiring users to install specialized software. It works by accepting file uploads or URLs through a REST API and converting them to viewable formats using backend processing. The tool abstracts file preview handling through a pluggable interface, allowing developers to add support for additional formats by implementing preview handlers for specific file types.
Organizations managing document repositories, content management systems, or file-sharing platforms should consider this tool if they need to display Office documents, PDFs, images, CAD files, 3D models, compressed archives, and media files to end users. The project suits teams already using Spring Boot who want to avoid building preview functionality from scratch. It requires either OpenOffice or LibreOffice as a backend dependency and optionally uses Redis for caching. The tool provides a straightforward deployment path on Windows, Linux, and macOS, though macOS requires manual installation of the office suite dependency.
The project maintains an active public demo instance and provides official documentation through its website. Development activity shows ongoing expansion of supported file formats across multiple categories including office suites, CAD systems, 3D model formats, and media types. The maintainers actively engage with users through documented support channels and encourage community contribution through the extensible preview interface design.
