Generic
To install ImageJ 1.40 on a computer with Java pre-installed, or to upgrade to the latest full distribution (including macros, plugins and LUTs), download ij140.zip (2MB) and extract the ImageJ directory. Use the Plugins>Utilities>Update ImageJ command in v1.40 to upgrade to the latest v1.41 pre-release.
Mac OS X
Download ImageJ 1.40 (2MB) 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 1.40 (43MB) for Linux x86. Includes the Sun Java 1.6.0_05 runtime and the ImageJ source code. (Instructions)Windows
Download ImageJ 1.40 bundled with Java 1.6.0_05 (21MB) or without Java (2.1MB). (Instructions)
Mac OS 9
Download ImageJ 1.36 (2.1M) as a double-clickable Mac OS 9 application. (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 77,000 lines of code in 242 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.