What is a PAR file?
PAR is short for "part". Each .par file describes one component designed in Siemens Solid Edge: its solid and surface bodies, the features and sketches used to create them, reference planes, colors, materials and custom properties. Because Solid Edge uses the Parasolid geometric kernel, the exact geometry inside a PAR file is Parasolid B-rep data.
The format is proprietary and its specification is not published. Other applications therefore need a dedicated reader to access the geometry and metadata of a PAR file, or must rely on neutral exports such as STEP or Parasolid X_T.
Native Solid Edge file types
| Extension | File type | Content |
| .par | Part | A single mechanical part: bodies, features, sketches, materials and properties |
| .psm | Sheet metal part | A part designed in the sheet metal environment, with flanges, bends and other sheet metal features |
| .asm | Assembly | The product structure, referencing .par, .psm and other .asm files |
| .dft | Draft | 2D drawings created from parts and assemblies |
What Is PAR Used For? Applications and Industry Use Cases
Solid Edge is widely used by machine builders, industrial equipment manufacturers and suppliers of mechanical components, so PAR files are common in these supply chains. They are exchanged with manufacturing partners, simulation teams and customers who work with different CAD systems.
For software developers, reading PAR files lets CAE applications mesh and simulate Solid Edge parts, CAM applications generate toolpaths, and viewers or collaboration tools display them, all without a Solid Edge license. Persistent names and custom properties help applications keep their own data linked to the model when a part is updated.
Challenges or Common Pitfalls
As with any proprietary format, the main difficulty is keeping up with each new Solid Edge release. A reader must interpret the file exactly as Solid Edge does to obtain the right geometry, colors and attributes.
Some Solid Edge features do not have a direct equivalent in other environments. Family tables, simplified bodies, enclosed components, assembly features and piping data are examples of content that may not translate, or may translate differently, so it is worth testing typical customer files early in a project.
Units are another point of attention. Applications should check which unit system the translator reports for Solid Edge data and convert values consistently, rather than assuming the units shown to the Solid Edge user.
How Spatial Helps
Our 3D InterOp SDK imports Solid Edge part (.par), sheet metal (.psm) and assembly (.asm) files, up to Solid Edge 2026, and delivers exact B-rep geometry to CGM Modeler, 3D ACIS Modeler or Parasolid. You can use your own Parasolid installation or our built-in Solid Edge Direct importer, which needs no setup.
Along with solid, sheet and wire bodies and free curves and points, 3D InterOp reads body and face colors, body names, persistent names on faces, edges and assembly instances, workplanes with their names and visibility, user-defined attributes and custom properties, and material properties such as density, Young's modulus and thermal conductivity. For assemblies, it extracts the full product structure.
Solid Edge files are imported only; writing them is not supported. Solid Edge assemblies are also supported by the Hidden Body Removal capability of our Data Prep technology, available in UConnect workflows.