There are many alternatives to Adobe Acrobat Reader for Windows if you are looking for a replacement. The best open source Windows alternative is SumatraPDF. If that doesn't suit you, our users have ranked more than 100 alternatives to Adobe Acrobat Reader and many of them are open source and available for Windows so hopefully you can find a suitable replacement. Other interesting open source Windows alternatives to Adobe Acrobat Reader are Okular, MuPDF, Xournal++ and Stirling PDF.
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.
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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.
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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.
United States
Handwritten note-taking and PDF annotation using pen input and pressure sensitivity, shape drawing, customizable toolbar layouts, image insertion, audio recording, multi-language options, LaTeX integration, and complete export in PDF or PNG formats across all platforms.
Locally hosted web application offering an interactive GUI to merge, split, reorganize, convert, compress, watermark, secure, sign, flatten, repair, extract images, detect blanks, apply OCR, set permissions, and enable file processing or API integration for PDFs.
United States
Butterfly is a note-taking app where your ideas come first. You can paint, add texts, and export them easily on every device. This app works on android, windows, linux, and in the web.
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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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Sioyek is a PDF viewer with minimal interface optimized for reading research papers and technical books.
United States
SpeedyNote is a fast, open-source note-taking application designed for stylus users who need iPad-quality annotation on budget hardware. Built with native C++ and Qt, it delivers 360Hz stylus input on hardware as modest as an Intel Celeron N4000 at 1.
Xpdf is a free PDF viewer and toolkit, including a text extractor, image converter, HTML converter, and more. Most of the tools are available as open source.
United States
Open-source PDF viewer and editor using Qt framework, featuring hardware-accelerated rendering, encryption, multithreading, text-to-speech, annotation tools, form filling, high-res monitor support, document compression, audio book conversion, and signature validation.
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