Native CAD interfaces
Direct support for the CAD formats listed here.
Parasolid Viewer
Open X_B and X_T files
intuitive & practical 3D without CAD expertise
affordable & universal many 3D/2D interfaces
Modern, easy-to-use CAD viewer
Cost-effective CAD converter for all formats
The 3D-Tool Viewer opens Parasolid X_T and X_B files without any additional CAD software.
The 3D-NativeCAD Converter converts Parasolid models to a wide range of formats such as STEP, IGES, JT, SAT, STL, OBJ, PLY, 3D-PDF, 3D-HTML, FBX, 3MF, and glTF.
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Stable, precise CAD data processing.
Windows support
Compatible with current Windows versions.
What are X_B and X_T files?
- Files with the X_B or X_T file extension contain 3D models in Parasolid format: X_B in compact binary form, X_T in readable text form (ASCII).
- Parasolid is a modeling kernel for 3D CAD systems developed by Unigraphics Solutions (UGS), which was later acquired by Siemens Digital Industries.
- The Parasolid modeling kernel is used in CAD, CAM, CEA, and data conversion software, including ›› Siemens NX, ›› SolidWorks and ›› Solid Edge.
- Parasolid offers more than 900 functions and supports multiple modeling techniques, including solid modeling, direct modeling, and freeform surfaces.
Parasolid versions
The British company Shape Data developed the Parasolid CAD kernel back in 1988. Shape Data has changed ownership several times since then and is now part of Siemens Digital Industries.
Parasolid is now available in version 38. (05/2026) For data exchange between Parasolid-based applications, Parasolid is the obvious first choice. Parasolid can also be used to exchange data between newer and older versions of a Parasolid-based CAD system. Most systems offer the option of exporting Parasolid data in older versions for this purpose.
The Parasolid version supported by your CAD application should be listed in the application documentation.
Parasolid specifics
- Units Parasolid units are always meters. When importing into a CAD program, the units should be scaled accordingly.
- Modeling kernel Parasolid is not only an exchange format, but also the modeling kernel of well-known CAD systems such as Siemens NX, SolidWorks, and Solid Edge. X_T and X_B files are therefore the preferred choice for data exchange between these systems and other systems that use the Parasolid kernel.
How do I open a Parasolid X_B or X_T file?
Typically, a CAD/CAM software that has a Parasolid interface is used for this, such as Siemens NX, SolidWorks and Solid Edge.
There are a few free Parasolid readers available for viewing a 3D design in Parasolid format, such as JT2Go. The focus here is on the presentation rather than the analysis of the designs.
The 3D-Tool CAD viewer is a Parasolid reader and opens all X_T versions from version 8. Professional measuring tools and analyses utilize the full potential of X_T data.
How can I convert a Parasolid X_B or X_T file?
Without CAD/CAM software with a Parasolid interface, the model must be exported from the original CAD system to another 3D exchange format or 3D visualization format (e.g. for 3D printing or design software such as Blender).
Converting from X_T to STEP, X_T to CATIA, X_T to OBJ, etc. is also possible with a 3D converter.
The 3D-NativeCAD Converter in 3D-Tool Premium converts Parasolid X_T and X_B and models from many other CAD systems reliably into the standard 3D exchange formats STEP, IGES, and SAT.
Try the Parasolid viewer and Parasolid converter for free
3D-Tool is a CAD Viewer with interfaces for common native CAD formats and 3D exchange formats. 3D-Tool offers professional measurement tools, draft analysis, and wall thickness analysis.
- Open, measure, annotate, and publish X_T and X_B files for the 3D-Tool Free Viewer or as 3D-PDF
- Open X_T and X_B files and save them as STL, 3DS, PLY, WRL, or OBJ
- Convert X_T and X_B files to JT, STEP, IGES, VDA, and SAT
- Convert Parasolid models into 3D product visualizations such as 3D-HTML, FBX, Collada, 3MF, and glTF
Simply download 3D-Tool, start it, and request a trial key. Test all functions, all interfaces, and the 3D-NativeCAD Converter for 14 days. Open and convert STEP, IGES, SAT, Parasolid, as well as CATIA, Siemens NX, Inventor, SolidWorks, and many other formats.
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