NETGEN is an automatic 3d tetrahedral mesh generator. It accepts input from constructive solid geometry (CSG) or boundary representation (BRep) from STL file format. The connection to a geometry kernel allows the handling of IGES and STEP files. NETGEN contains modules for mesh optimization and hierarchical mesh refinement. Netgen is open source based on the LGPL license. It is available for Unix/Linux and Windows.

NETGEN was developed mainly by Joachim Schöberl within project grants from the Austrian Science Fund FWF ( Special Research Project "Numerical and Symbolic Scientific Computing", Start Project "hp-FEM) at the Johannes Kepler University Linz. Significant contributions were made by Johannes Gerstmayr (STL geometry) Robert Gaisbauer (OpenCascade interface).