Platform Independent
To install ImageJ 1.41 on a computer with Java pre-installed, or to upgrade to the latest full distribution (including macros, plugins and LUTs), download ij141.zip (2MB) and extract the ImageJ directory. Use the Help>Update ImageJ command in v1.41 to upgrade to the latest pre-release version.
Mac OS X
Download ImageJ 1.41 (3MB) as a double-clickable Mac OS X application. Includes ImageJ64, which runs in 64-bit mode on Intel Macs running Leopard. (Instructions)
Linux x86
Download ImageJ 1.41 (43MB) for Linux x86. Includes the Sun Java 1.6.0_10 runtime and the ImageJ source code. (Instructions)Windows
Download ImageJ 1.41 bundled with Java 1.6.0_10 (26MB) or without Java (2.1MB). (Instructions)Documentation
Download the ImageJ documentation (25MB), in HTML format, as a compressed zip archive. The JavaDoc API documentation (567K) is also available.
Source Code
The ImageJ Java source consists of 85,000 lines of code in 258 files. It is available as a zip archive and as colorized and browsable HTML.
Example Images
31 downloadable sample images and stacks are available in ImageJ's File>Open Samples submenu. These images, and more, are also available as a 8.2MB zip archive.