napari is a fast, interactive, multi-dimensional image viewer for Python. It’s designed for browsing, annotating, and analyzing large multi-dimensional images. It’s built on top of Qt5 (for the GUI), VisPy (for performant GPU-based rendering), and the scientific Python stack (numpy, scipy).
napari can be installed on most macOS, Linux, and Windows systems with Python 3.7 and 3.8 using pip:
pip install 'napari[all]'
napari needs a library called Qt to run its user
interface (UI). In Python, there are two alternative libraries to run this,
and PySide2. By default, we don’t choose
for you, and simply running
pip install napari will not install either. You
might already have one of them installed in your environment, thanks to other
scientific packages such as Spyder or matplotlib. If neither is available,
running napari will result in an error message asking you to install one of
To install napari with a specific UI framework, you can use
pip install 'napari[pyqt5]' # or pip install 'napari[pyside2]' # or pip install 'napari[all]'
This last option (
pip install napari[all]) will choose a framework for
you — currently PyQt5, but this could change in the future.