Sioyek

Sioyek is a free, open-source PDF viewer designed specifically for reading research papers, textbooks, and technical documents. It emphasizes fast navigation, keyboard-driven controls, and efficient access to references within lengthy publications. Its Smart Jump functionality allows readers to navigate between citations, figures, and their corresponding references. Users can preview referenced content without permanently leaving their current reading position. The application supports searchable highlights, bookmarks, and named locations for organizing research. Its portal system enables simultaneous viewing of connected document sections and references. Available for Windows, macOS, and Linux, Sioyek combines advanced document navigation with a lightweight, customizable reading interface.