calibre Alternatives for Linux

Okular is a versatile document viewer from the KDE community, supporting a wide array of file formats including PDF, EPUB, DjVu, and TIFF. It offers intuitive navigation, robust annotation tools, and features like text selection and saving, making it a powerful tool for handling diverse document types.

FBReader is a versatile and free ebook reader application supporting multiple formats including ePub, Kindle azw3, and fb2. It offers a customizable reading experience across different platforms with features like library management, synchronization, and text-to-speech.

Polar is a powerful desktop application designed to serve as an integrated reading environment. It allows users to actively read, annotate PDFs and web pages, create flashcards for spaced repetition learning, organize their digital library, and track their reading and learning progress. It's built for focused and deep engagement with digital content.

Cool Reader is a highly configurable and lightweight eBook viewer designed for comfortable reading on various devices. It supports multiple formats including EPUB and DOCBOOK, offers extensive customization options for interface and reading experience, and includes useful features like library management, annotations, and sync capabilities.

EPUBReader is a lightweight and efficient browser extension that allows users to open and read EPUB e-books directly within their web browser. It provides a simple and intuitive reading experience without requiring external software.