The best open source alternative to Foxit PDF Reader is SumatraPDF. If that doesn't suit you, our users have ranked more than 100 alternatives to Foxit PDF Reader and many of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Foxit PDF Reader are Okular, Evince, MuPDF and Firefox PDF Viewer (PDF.js).
This free, open-source viewer for Windows supports multiple formats like PDF, eBooks (ePub, Mobi), CHM, and Comic Books (CBZ, CBR). Prioritizing simplicity and speed, it offers a lightweight, portable design with a minimalist interface, catering to users seeking fast and efficient document viewing.
Multi-platform document viewer supporting PDF, ePub, comics, images, and Markdown with annotation, digital signature verification, tabbed interface, sidebar navigation, text selection, text-to-speech, magnifier, search, dark mode, and plugin support.
Supports viewing and editing PDF annotations, displays multiple formats such as PDF, Postscript, DjVu, comic books, TIFF, DVI, XPS, remembers per-document zoom and position, features search, table-of-contents navigation, SyncTeX integration, and printing.
MuPDF offers a highly versatile PDF, XPS, and eBook interpreter, customizable as a renderer, viewer, or toolkit. Features include digital signatures, redactions, form filling, annotations, and page manipulation, ideal for mobile, eBooks, and embedded apps supporting Java, C++, and Python.
PDF Viewer (aka pdf.js) is a new revolutionary extension using web standard technologies that allows you to display within Mozilla Firefox almost all PDF files found on the web without a plugin.
Sioyek is a PDF viewer with minimal interface optimized for reading research papers and technical books.
PDF viewer for macOS supports scientific papers, annotations, highlights, bookmarks, split view, exporting notes, AppleScript, multiple annotation types, bibliography integration, full-screen, search, and compatibility with various macOS versions.
Xournal is an application for notetaking, sketching, keeping a journal using a stylus. It is free software (GNU GPL) and runs on Linux (recent distributions), Windows and other GTK+/Gnome platforms.
Document Viewer is a highly customizable document viewer for Android, fork of the last GPL version of EBookDroid .
A document viewer for the GNOME desktop. You can view, search or annotate documents in many different formats.
High-performance viewer for documents and images offering split tabs, customizable single or book layouts, portals for side-by-side sections, instant search, line highlight, annotation tools, link hints, searchable highlights, session management, and TOML config.
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Sumatra is a good alternative because 1) wide range of formats supported, and 2) it's open source.