Molekel is a free software multiplatform molecular visualization program. It was originally developed at the University of Geneva by Peter F. Flükiger in the 1990s for Silicon Graphics Computers. In 1998, Stefan Portmann took over responsibility and released Version 3.0. Version 4.0 was a nearly platform independent version. Further developments lead to version 4.3, before Stefan Portman moved on and ceased to develop the codes. In 2006, the Swiss National Supercomputing Centre (CSCS) restarted the project and version 5.0 was released on 21 December 2006.