MuPDF 1.25

About MuPDF

MuPDF is an ultra-fast, lightweight and high-quality document viewer and library. It is widely regarded as one of the fastest PDF renderers available.

In version 1.25 (May 2026), MuPDF received major performance improvements and better Windows 11 compatibility.

The program is completely free, open-source and contains no ads or telemetry.

MuPDF is a high-performance PDF, EPUB, XPS and CBZ rendering library and viewer developed by Artifex Software. It is widely considered one of the fastest and most efficient document rendering engines in the world. Many popular PDF viewers, including SumatraPDF, are built on top of the MuPDF library because of its exceptional speed and quality.

The core strength of MuPDF lies in its custom-built rendering engine that is specifically optimized for speed and low memory usage. Unlike many other PDF viewers that use heavy frameworks or full Adobe-compatible engines, MuPDF was designed from the ground up to be as fast and lightweight as possible while maintaining excellent rendering accuracy and quality.

This makes MuPDF ideal for situations where performance matters most — opening large PDF files, running on low-resource devices, or embedding PDF viewing capabilities into other applications. Developers frequently choose MuPDF for their projects because of its small footprint and high speed.

MuPDF supports not only PDF but also EPUB e-books, XPS documents, comic book archives (CBZ) and several other formats. The rendering quality is excellent, with high-quality anti-aliasing, accurate font rendering, and proper handling of complex layouts, transparency, and advanced PDF features.

The viewer itself is very simple and clean. It focuses on fast document viewing with minimal interface elements. You can open documents, navigate pages, search text, zoom, and perform basic annotations. For users who want more features, there are several viewers built on top of the MuPDF engine, such as SumatraPDF, which add a more user-friendly interface while keeping the core speed of MuPDF.

Being open-source, MuPDF is actively developed and regularly updated. Version 1.25 (May 2026) brought major performance improvements, better support for modern Windows 11 features, improved rendering quality on high-DPI displays, and enhanced compatibility with the latest PDF standards.

One of the biggest advantages of MuPDF is its extremely small size and low resource usage. The library and viewer can run on very low-end hardware and embedded devices, making it popular in industrial and specialized applications where resources are limited.

In 2026, with the increasing size of digital documents and the need for fast document viewing on various devices, MuPDF continues to be one of the most respected and widely used document rendering solutions. Its combination of speed, quality, and open-source nature makes it a favorite among developers and power users alike.

Key Features

• Extremely fast PDF, EPUB, XPS and CBZ rendering
• Very small size and low memory usage
• High-quality anti-aliased rendering
• Simple and clean interface
• Annotation and form support
• Command-line tools available
• Portable version available
• Completely free and open source