What is ImageJ?

Imagej2-icon.png ImageJ is an open source image processing program for multidimensional image data with a focus on scientific imaging.

What is Fiji?

Fiji-icon.png Fiji Is Just ImageJ—a "batteries-included" distribution of ImageJ which includes many useful plugins contributed by the community.

What does ImageJ provide?

Application A user interface with functions to load, display, and save images.
Techniques Image processing, colocalization, deconvolution, registration, segmentation, tracking, visualization and much more.
Plugins A powerful mechanism for extending ImageJ in all kinds of useful ways.
Scripting Automated, reproducible workflows via scripts and macros, including headless on a remote server or cluster.
Forum A vibrant, diverse, and helpful user community that gives rise to insightful scientific exchanges.

ImageJ's extensibility is the root of its effectiveness: many advanced image-processing methods are not provided by the core application, but rather are plugins written by specialists in specific fields, made available via update sites.

How do I get started?