CalculiX for Windows

The solver, CCX, was written and is maintained by Guido Dhondt. The pre and post processor, CGX, was written and is maintained by Klaus Wittig.

The source code, Linux builds, documentation, tests and other resources for CalculiX are available for download at

Convergent Mechanical Solutions has bundled this build for CCX and CGX as well as the documentation, examples and test suite. There have been some changes from the original source, and those modified source files are included. Some scripts were also added. These are available at

Getting Started

A tutorial for the entire suite of tools in CalculiX for Windows is in work. An in-work version is available with this build.


If the CalculiX file types have been associated with CalculiX, then the following actions are defined:

File typeOpen (double click)Edit
CCX input (.inp)Open in CGXOpen in SciTE
CCX results (.frd)Open in CGX
CGX geometry (.fbd)Open in CGXOpen in SciTE

The Edit actions are only set if SciTE is installed along with CalculiX for Windows. Associating file types is an installation option.

Complementary Tools

Tools added to this build by Convergent Mechanical Solutions include:


    A custom build of SciTE has been included in all current builds of CalculiX for Windows. The installation of SciTE is optional. This version includes a lexer for FBD files and minor changes to the code base to allow for the level of interactivity required for running CGX from within the editor. It also includes an Abaqus/CCX lexer and an APDL (Ansys Parametric Design Language) lexer. The function keys perform different tasks depending on the type of file that is active.

    File typeCtrl-F10F10
    CCX input (.inp)Solve in CCXOpen in CGX
    CGX geometry (.fbd) Open in CGX

    The output, including the interactive feedback from CGX, is written to an output window in SciTE.

    SciTE can be started from the short cut in the Start menu: [Start][Programs][CalculiX][SciTE]

    OCC Viewer

    The OCC Viewer is a geometry viewer shipped with the extended version of CalculiX for Windows. It views IGES, STEP, CSFBD and BREP files and can save as FBD, IGES, STEP, CSFBD, BREP, STL and VRML. It can also export a bitmap or PNG image of the current view. The OCCviewer.bat file has an option to invert the colors on export (set OCCVIEWER_NEGATE_IMAGES=1).

    To navigate the model, press the key and use the three mouse buttons to zoom, pan and rotate the geometry. Multiple geometry files can be read into the same window and each can have its color and transparency set independently.



    This application is a graphical user interface for interacting with CCX and CGX. Features include: launching CCX and CGX jobs, getting help and modifying your start-up script. The CCX output is captured and handled by the application, but CGX is spawned as a new process and the output goes to a command window which is optionally closed at the end of the session. There is also a wizard to guide the user through the various CAE data translators. This is only available in the extended version of CalculiX for Windows.

    The launcher can be started from the short cut in the Start menu: [Start][Programs][CalculiX][CalculiX Launcher]


    transform & translate

    These applications call various CAD and CAE data translators and other tools. The translations of the CAD and CAE are done with a unified command line syntax or with the Data Translator Wizard incorporated into the Launcher. The translators are:

    • VDA/FS to FBD written by contributors to the open source project

    • A C++ port of a contributed ACIS to FBD translator

    • A translation tool from IGES and STEP to FBD, IGES, STEP, STL and VRML that was written by Convergent Mechanical Solutions.

    • Abaqus INP format to CCX INP format (supports *PARAMETER, *NGEN, *ELGEN and more)

    • Gmsh format to Abaqus or CCX INP format

    The transformation functionalities, the last three translations and the wizard are only available in the extended version of CalculiX for Windows.

    Some of these translation tools are not complete. For more information about the supported entities reference Convergent Mechanical Solutions' translators page. If there is a CAD or CAE I/O data format that is not currently supported or not supported sufficiently for your project please submit a feature request to

        transform -abq inFile -offsetNum nNum elNum outFile
        transform -abq inFile -props
        translate ( -abq| -ccx) inFile ( -ccx|-gmsh) outFile
        translate  -gmsh        inFile ( -abq| -ccx) outFile elemDim
        translate (-acis| -vda) inFile   -fbd        outFile
        translate (-iges|-step) inFile   -fbd        outFile
        translate (-iges|-step) inFile (-iges|-step) outFile
        translate (-iges|-step) inFile ( -stl|-vrml) outFile
            Use to filter element topologies. Valid values are: 
            where: 0=point, 1=line, 2=surface, 3=volume


    This application is used as a way to quickly get help from the command line. The default execution prints the usage of all the applications ("advise" or "advise usage"). To display the documentation, type: "advise docs".

        advise [usage|docs]
         usage    prints usage for all applications (default)
         docs     launches the help file for CalculiX

Customizing Environment

The [Start][Programs][CalculiX][CalculiX Command] short cut opens a Windows command prompt with all the required environment variables set for CalculiX and additional tools and testing scripts. These variables can be modified by editing the script: C:\Program Files\CalculiX\common\site\cmdStartup.bat

The launcher [File] menu has an option for opening this file for editing. If the environment has been modified while Launcher is running, it can be refreshed in the current session by using the menu option [File][Reread Startup Script] or typing -r.

A common variable to change is the working directory where the CalculiX Command window opens. This can be changed by modifying:

   set HOME=C:\Temp\work

The text editor called by the launcher is also defined by in the startup script. The default editor is Notepad, unless SciTE was installed.

   set CALCULIX_EDITOR=%SystemRoot%\system32\notepad.exe


   set CALCULIX_EDITOR=C:\PROGRA~1\wscite\SciTE.exe