Gmsh

Free plan APILinuxMacWindows

What Gmsh is

Gmsh is a free, open-source 3D finite element mesh generator with a built-in CAD engine and post-processor. Its four modules handle geometry, meshing, solver functions, and post-processing. Geometry can use built-in or OpenCASCADE CAD kernels, including constructive solid geometry operations. The meshing module creates one-, two-, and three-dimensional meshes with elements such as triangles, quadrangles, tetrahedra, prisms, hexahedra, and pyramids. Users can work through a graphical interface, command line, .geo files, or APIs for C++, C, Python, Julia, and Fortran. An ONELAB server can drive external solvers such as GetDP, and optional Netgen and Mmg3d libraries can be connected. Binaries, source code, an SDK, and pip installation instructions are available for Windows, Linux, and macOS. Releases require Windows 10 or later, Linux glibc 2.28 or later, or specified newer macOS versions. Gmsh uses GPL version 2 or later, with restrictions on closed-source distributed integration.

Who it suits

Gmsh suits engineers, researchers, and developers who need CAD, finite-element meshing, solver connections, or post-processing. Its interfaces and APIs support both interactive and scripted workflows.

What it does well

Free open-source distribution
Generates 1D, 2D, and 3D meshes
Built-in and OpenCASCADE CAD kernels
Graphical, command-line, scripting, and API use
Binaries available for major desktop systems

What to know first

Closed-source distributed integration requires a commercial license
Discrete model entities lack geometric operations
Binary releases require specified operating systems
No sculpting or animation tools

Plans

Plan	Billed and limits	Price
Gmsh (GPL)	Free to use and redistribute; restrictions apply to distribution and closed-source integration	Free

As gmsh.info lists them, read 11 Oct 2026. The maker's own page has the final word.

Verdict

Gmsh provides a broad geometry, meshing, solver, and post-processing toolkit across desktop platforms and programming APIs. Its GPL terms and discrete-geometry limitation matter when planning commercial distribution or STL-based workflows.

Facts from Gmsh's own pages

Animation tools: No · gmsh.info, 22 Sept 2026
CAD: The geometry module supports built-in and OpenCASCADE CAD kernels, including constructive solid geometry operations through OpenCASCADE. · gmsh.info, 11 Oct 2026
Distribution: The site offers binaries for Windows, Linux and macOS, source code, and an SDK; it also documents a pip installation. · gmsh.info, 11 Oct 2026
Free plan: Yes · gmsh.info, 22 Sept 2026
Known limitation: Gmsh does not perform geometric operations on discrete model entities such as STL-defined entities, though they can be reparametrized for meshing. · gmsh.info, 11 Oct 2026
License: Gmsh is distributed under the GNU General Public License version 2 or later, with an exception for easier linking with external libraries. · gmsh.info, 11 Oct 2026
License restriction: The site says this version cannot be integrated, in whole or in part, into closed-source software intended for distribution; a commercial license is required for that use or to sell a modified closed-source version. · gmsh.info, 11 Oct 2026
Meshing: The mesh module generates 1D, 2D and 3D meshes, including triangles, quadrangles, tetrahedra, prisms, hexahedra and pyramids. · gmsh.info, 11 Oct 2026
Modules: Its four modules cover geometry, meshing, solver functions and post-processing. · gmsh.info, 11 Oct 2026
Parametric modeling: Yes · gmsh.info, 22 Sept 2026
Platform access: desktop · gmsh.info, 22 Sept 2026
3D print export: Yes · gmsh.info, 22 Sept 2026
Purpose: Gmsh is an open-source 3D finite element mesh generator with a built-in CAD engine and post-processor. · gmsh.info, 11 Oct 2026
Related tools: Gmsh uses OpenCASCADE for constructive geometry and can interface with the optional Netgen and Mmg3d mesh libraries. · gmsh.info, 11 Oct 2026
Sculpting tools: No · gmsh.info, 22 Sept 2026
Solver integration: Gmsh implements an ONELAB server that can drive external solvers such as the GetDP finite element solver. · gmsh.info, 11 Oct 2026
Support: The site directs users to read the tutorial and FAQ before sending questions or bug reports, and asks users to report issues through its issue tracker. · gmsh.info, 11 Oct 2026
System requirements: The listed binary releases require Windows 10 or later, Linux with glibc 2.28 or later, macOS 10.15 or later on Intel, or macOS 12 or later on Apple silicon. · gmsh.info, 11 Oct 2026
Ways to use: Gmsh can be controlled through a graphical interface, command line, .geo scripting files, or APIs for C++, C, Python, Julia and Fortran. · gmsh.info, 11 Oct 2026

Where Gmsh stands on Freedom251

3D modeling software#69 of 147