Honoring the C Engine Legacy While Embracing Pythonic Ease

If you've spent any time with PyMuPDF, you've probably noticed something that looks like a quirk: for years the canonical import was import fitz. Where does fitz come from? It sounds like a surname or a shorthand. The origin is actually a small piece of software history and once you know it then it hopefully stops feeling like an oddity.

The Name Behind the Name

MuPDF is the C library at the heart of PyMuPDF and was created at Artifex Software in the mid 2000’s. During its early development, the internal project codename was Fitz.

When PyMuPDF was created as a Python binding for MuPDF, the fitz name was carried forward as the Python module name. It wasn't branding or marketing. It was the engineering team saying: this thing you're importing is, at its core, is MuPDF.

What the Name Actually Tells You

Here's why this matters beyond trivia.

PyMuPDF is not a PDF toolkit that happens to use MuPDF somewhere under the hood. It is, by design, a thin and direct bridge to MuPDF's C engine. When you call fitz.open(), parse a page, extract text, render pixels, or manipulate annotations, you are calling into one of the most battle-tested, high-performance document rendering engines in existence. MuPDF powers Artifex's own commercial products, it's embedded in countless PDF solutions, and it's been refined over more than fifteen years of production use.

The fitz import was never an abstraction that hid the engine. It was an acknowledgment of it.

Speed Comes from C, Not from Python

The industry recognizes that C gives you performance boosts. Consider Elon Musk’s rockets & satellites:

This is also one of PyMuPDF's strongest and most defensible advantages: C performance that Python-native PDF libraries simply cannot match, because the heavy lifting isn't done in Python at all. Essentially our “flight code” is C and our pythonic interface allies for the access and control.

Rendering a page to a pixmap? MuPDF's C rendering pipeline. Text extraction with position data? MuPDF's layout engine. Font handling, color space management, transparency compositing? All C. PyMuPDF wraps these capabilities with a clean, Pythonic API, but it doesn't reimplement them. The result is that PyMuPDF routinely outperforms alternatives by significant margins on extraction and rendering tasks — not because of clever Python, but because it's delegating to an engine that was built from the ground up for this work.

When developers benchmark PyMuPDF against other Python PDF libraries and find it faster, they're really seeing MuPDF's performance expressed through Python bindings.

The Rebranding Didn't Change the Architecture

In recent versions, import pymupdf works as the primary import, and the PyMuPDF name is front and center. That's a sensible move for discoverability — fitz was genuinely confusing to people encountering the library for the first time. But the architecture hasn't changed. fitz still works as an alias. More importantly, the relationship it named is still the defining characteristic of the library.

PyMuPDF's power comes directly from MuPDF's C engine. The fitz name was always a quiet way of saying exactly that, a way of honoring the origin, acknowledging the dependency, and being honest about where the performance actually lives.

Why This Should Matter to You

If you're evaluating Python libraries for document processing, understanding this architecture matters for your decision. Libraries that implement their own Python-level PDF parsing face a fundamental ceiling: Python isn't as fast as C, and PDFs can be complex. PyMuPDF sidesteps that ceiling entirely by not trying to compete with C in Python.

It also means PyMuPDF inherits MuPDF's correctness. PDF is a notoriously forgiving-but-tricky format, and years of real-world edge cases have been ironed out in MuPDF. You get that history for free.

The name fitz was a breadcrumb left by engineers who knew exactly what they'd built and wanted to be transparent about it. Follow the breadcrumb, and you find the engine that makes PyMuPDF worth using.