From MarcsHomepage


Rasmol was one of the first really useful molecule-viewers around for the Windows-PC. It has been written by Roger A. Sayle as part of a project for rasterized display of molecule-data on a workstation. Rasmol is surely the fastest and maybe best known molecule-viewer on the net, nowadays available for virtually all computer-systems, even weird ones like the NeXTStep or Acorn Archimedes. There are some "flavours" of the program with different enhancements (like a better mouse-driven interface or some extra abilities). I will only talk about the original Rasmol here.

User Interface


The user-interface of Rasmol consists in a bunch of pull down-menus for the basic tasks and a command-line prompt (a independent window under Windows) for the more sophisticated tasks. Rasmol has an easy to learn command-language with history-buffer, imho much easier than the Molmol or Pymol scripting. Rasmol can view and manipulate the appearance of the molecule, making it possible to enhance different aspects of a data-set. One can select single atoms, residues, groups of atoms/residues. The big advantage of Rasmol over it´s competitors is it´s unbeaten speed of display even on slow machines without a good 3D-accelerator and it´s ability to load and show most types of molecules correctly (A thing Molmol and sometimes WebLabViewer and SwissPDBViewer can´t do all the times). The drawback of the speed is a low image-quality due to the software-renderer. There is the possibility to create an output-file for another program which generates better- looking images in Postscript-format, namely Molscript. The most recent version has Povray-exort capabilities, which are very limited though.

Another disadvantage is that it can only load and display one single dataset at a time (but there´s an enhanced version, which can load multiple molecules in one window).

Although Rasmol is really outdated by now and not under active development any more, Rasmol is still one of the best choices for realtime molecule display, if you don't own a fast computer with a good 3D-card or don't need advanced editing and rendering features.


The main features of Rasmol are listed below, for a full review of the program, see the excellent Rasmol-homepage , maintained by Professor Eric Martz.

  • Display, rotation, translation, scaling of one molecular-data-set
  • Selection and manipulation (deleting) of atoms, residues, and whole molecules
  • Detailed and structural view of residues and atoms
  • Creation of script-controlled "movies" with annotations and interactive control
  • Output of Molscript-files and rasterized images in various formats
  • It has been announced, that the next Version of Rasmol will support POVRay-output.