A number of documents, including an electronic book, provide additional details about the Toolkit. For Unix users who would like to take advantage of the program's newer features, Cn3D can be built as part of the NCBI Toolkit, which contains the Cn3D source code and make files (requires wxWidgets). However, an earlier release, Cn3D 4.1 for Unix, is still available. Unfortunately, NCBI can no longer support a Unix version of Cn3D.

Once you have installed the program files for your platform, follow the instructions below to set up your browser to launch Cn3D from the NCBI web pages (if not already done by the installer). In order to run Cn3D on MacOS versions OSX 10.15 and up, users need to install a replacement for the X11 windowing system, such as the open-source version of the X.Org X server XQuartz.

Note for Gatekeeper-enabled Macs (OSX 10.7.5 and up).

To install the free Cn3D macromolecular structure viewing program, select your operating system: Installing the Cn3D 4.3.1 3-D structure viewer

Structure download free