As a company that specializes in CAD Translation, we often get questions about a wide range of CAD file extensions; to make this easier on our customers, we’ve compiled a list of the most common Brep and Visrep formats.
Brep stands for Boundary Representation, which is a true CAD format. Visrep stands for Visual Representation, which is a polygonal or tesellated format. We are including both Brep and Visrep formats in this listing since there is often confusion as to which is which.
|Software||Extensions||Brep or Visrep||Notes|
|3D PDF||Visrep||3D PDF is a great format for sharing geometry with those who do not have access to CAD systems or CAD viewers; all that’s required is the Adobe Reader, which is already on almost all PCs.|
|3D XML||.3DXML||Visrep||3D XML is a visualization format developed by Dassault Systemes.|
|3DS Max Files||.3DS, .MAX||Visrep||.3DS files contain mesh or nurbs information; .MAX files contain all scene information, including mesh data.|
|ACIS Model & Assembly Files||.SAT, .ASAT, .SAB, .ASAB||Brep||ACIS is a geometric modeling kernel used in many CAD applications. .SAT and .SAB files are part files, .ASAT and .ASAB files are assembly files. Files that end with B are binary.|
|Alias Model file||.WIRE||Visrep|
|AutoCAD Drawing Files||.DWG, .DXF||Brep and Visrep||.DWG files are binary, .DXF files are ASCII. Both formats can contain both Brep and Visrep geometry.|
|Autodesk Filmbox Format||.FBX||Visrep||Primarily used for exporting mesh, material and animation data to game engines.|
|CADKEY File||.PRT, .CKD||Brep||CADKEY is now known as KeyCreator.|
|CATIA V4 Part & Assembly Files||.MODEL||Brep||.MODEL files can represent both parts and assemblies.|
|CATIA V5 Parts and Assemblies||.CATPart, .CATProduct||Brep|
|CATIA V5 Graphical Representation File||.CGR||Visrep|
|CATIA V6 Part and Assembly Files||.CATPart & .CATProduct||Brep||File format is similar to V5 files.|
|Collada Object Format||.DAE||Visrep|
|Creo Part and Assembly Files||.DRW, .PRT, .ASM||Brep||.DRW are drawing files, .PRT are part files, and .ASM files are assembly files. Creo was formerly known as Pro/Engineer.|
|Fusion 360 Files||.F3Z, .F3D, .CAM360||Brep||.F3Z files are archive files, .F3D are part files, and .CAM360 are toolpath archive files.|
|Generic CADD Files||.CMP, .GCD||Brep||.CMP files are component files, .GCD are drawing files.|
|Geomagic GeomView Design File||.WRP|
|Gerber Printed Circuit Board File||.GBX|
|HOOPS Metafile Format File||.HMF||Visrep|
|HOOPS Stream Format File||.HSF||Visrep||IGES||.IGS, .IGES||Brep||IGES files are predominately surface files, though the definition does allow for solid models. Read more about why to avoid IGES, and alternatives to IGES.||Inventor||.IPT, .IAM||Brep||.IPT files are part files, .IAM files are assembly files.||IronCAD||.ICS||Brep||JT||.JT||Both||JT, created by Siemens / NX, is unusual in that it can contain both Brep and Visrep content. JT is also compressed about 8:1, so it is a good visualization format for large assemblies.|
|KeyCreator Part & Assembly Files||.CKD, CDL||Brep||KeyCreator was formerly CADKey; .CKD files are for parts and assemblies, .CDL files are for Wireframe Design files.|
|Kubotek Design Container File||.CKD||Brep|
|Lightwave Object File||.LWO||Visrep|
|Microstation Design Files||.DGN||Brep|
|Modo Scene Format||.LXO||Visrep|
|Navisworks Files||.NWC, .NWD, .NWF||.NWC files are cache files, .NWD are documents, .NWF are file sets.|
|NX Part and Assembly Files||.PRT||Brep||NX was formerly Unigraphics; one confusing aspect to NX .PRT files is that the same extension is used for both parts and assemblies.|
|Parasolid Model File||.X_T, .X_B||Brep||Parasolid is the geometric modeling kernel used for SOLIDWORKS, Solid Edge, and many other CAD solutions; read more about Parasolid here.|
|Pro/Engineer Granite File||.G||Brep||Granite is the geometric modeling kernel behind all Pro/E and Creo products.|
|Pro/Engineer Part and Assembly Files||.PRT, .ASM||Brep||Pro/Engineer is now known as Creo|
|Rhino 3D Model File||.3DM||Brep||Rhino is primarily a freeform NURBS surface modeler specializing in complex surface creation.|
|SDRC||.PRT, .ASM||Brep||SDRC was purchased by EDS in 2001, and then by Siemens in 2007, and is no longer in existence as a CAD solution. Since version 11, I-DEAS was able to export parts and assemblies as Parasolid files to provide interoperability with NX.|
|SMlib||.SMS, .IWB, IWP||Brep||SMlib is created by Solid Modeling Solutions; these files are geometric modeling kernels used in a range of CAD applications.|
|Solid Edge||.PAR, .ASM, .PSM||Brep||.PAR files are part files, .ASM files are assembly files. Solid Edge is made by Siemens.|
|SOLIDWORKS eDrawing File||.EDRW|
|SOLIDWORKS Part & Assembly Files||.SLDPRT, .SLDASM||Brep||.SLDPRT files are parts, .SLDASM files are assemblies. SOLIDWORKS is owned by Dassault.|
|STEP||.STEP, .STP||Brep||STEP is the most popular neutral CAD format in the world today.|
|Stereolithography Files||.STL||Visrep||.STL files are widely used for 3D printing.|
|Unigraphics Part & Assembly Files||.PRT||Brep||Unigraphics is now known as NX; one confusing aspect to Unigraphics and NX .PRT files is that the same extension is used for both parts and assemblies.|
|Wavefront||.OBJ||Visrep||.OBJ is widely used by modeling and animation solutions such as Maya and 3DS Max for transfering polygonal meshes.|
|ZBrush Files||.ZBR, .ZPR||Visrep||ZBrush is a modeling and texturing application.|
|ZW3D||.Z3||Brep||ZW3D is made by ZWSoft.|
|VRML||.WRL||Visrep||VRML stands for Virtual Reality Modeling Language.|
|WebGL||.HTML||Visrep||WebGL stands for Web Graphics Library. This format allows viewing and rotating in any HTML5-compliant browser with no plugins needed, and is suitable for online parts libraries.|
Many of these files can be read and written by TransMagic products; to see which ones, check out our CAD Formats page. Want to give TransMagic a try? Click here to try the free 7-day eval of TransMagic.
Brep vs Visrep Models – A comparison between Brep and Visrep models which looks at pros and cons of each.
The CAD Format Ladder Part 1 – A system to determine the best format for each situation.
The CAD Format Ladder Part 2 – Part 2, determining the best format for each situation.
What Format Do I Have Here? – Using the contents of the CAD file to determine the format and version.