Native CAD interfaces
Direct support for the CAD formats listed here.
Parasolid Viewer
Open X_B and X_T files
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The 3D-Tool Viewer opens Parasolid X_T and X_B files without any additional CAD software.
The 3D-NativeCAD Converter in 3D-Tool Premium converts Parasolid models to CAD exchange formats such as STEP, IGES, JT, and SAT. It also supports visualization formats such as STL, OBJ, 3D-PDF, 3D-HTML, FBX, 3MF, and glTF.
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Windows support
Compatible with current Windows versions.
Received a File Format You Don't Recognize
A file with the X_T or X_B extension is a Parasolid model - for anyone receiving one for the first time, often an unfamiliar format with no obvious CAD program behind it. The 3D-Tool Viewer opens X_T and X_B files directly, without the original CAD program installed.
That makes it possible to view, measure, and check the model for completeness right away, before reusing it in your own design. When another format is needed, the 3D-NativeCAD Converter transfers the file to, for example, STEP or IGES.
What are Parasolid 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. The British company Shape Data originally developed the Parasolid modeling kernel. Parasolid later belonged to Unigraphics Solutions (UGS). Today, Parasolid belongs to Siemens Digital Industries.
- The Parasolid modeling kernel is used by CAD, CAM, CAE, and data conversion software. These include Designcenter (Siemens NX), SolidWorks, and Designcenter Solid Edge. Parasolid offers more than 900 functions. The modeling kernel supports several 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 the first choice for exchanging data between Parasolid-based applications. This also applies to exchange between newer and older versions of a Parasolid-based CAD system. Most systems can export Parasolid data in older versions for this purpose. The Parasolid version supported by your CAD application is usually 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 the modeling kernel of Designcenter (Siemens NX), SolidWorks, and Designcenter Solid Edge. Therefore, X_T and X_B are the preferred choice for data exchange between these three and other Parasolid-based systems.
How do I open a Parasolid X_B or X_T file?
Open Parasolid X_B and X_T files with CAD/CAM software that has a Parasolid interface. Examples include Designcenter (Siemens NX), SolidWorks, and Designcenter Solid Edge. A few free Parasolid readers, such as JT2Go, are available for viewing a 3D design in Parasolid format. They focus on presentation rather than analysis of the designs.
The 3D-Tool CAD Viewer is a Parasolid reader and opens all X_T versions from version 8. Professional measurement tools and analyses utilize the full potential of X_T data.
How can I convert a Parasolid X_B or X_T file?
Convert Parasolid X_T and X_B files with a 3D converter, for example X_T to STEP, X_T to JT, or X_T to OBJ. 3D-Tool Premium includes the 3D-NativeCAD Converter. The 3D-NativeCAD Converter converts Parasolid X_T and X_B as well as native models from many common CAD systems to the 3D exchange formats STEP, IGES, JT, and SAT. Most CAD/CAM programs support these formats.
Without a 3D converter or CAD/CAM software with a Parasolid interface, the only route is through the original CAD system. There, the model must be exported to another 3D exchange format or 3D visualization format (for example for 3D printing or design software such as Blender).
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, and SAT
- Convert Parasolid models into 3D product visualizations such as 3D-HTML, FBX, 3MF, and glTF
Download 3D-Tool, start the program, and request a trial key. Try all features, all interfaces, and the 3D-NativeCAD Converter free of charge for 14 days. Open and convert JT, STEP, IGES, SAT, Parasolid, as well as formats from CATIA, Designcenter (Siemens NX), Inventor, SolidWorks, and other CAD systems.
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Frequently Asked Questions (FAQ)
What is the difference between X_T and X_B files?
Both are Parasolid exchange formats. X_T stores the 3D model in readable text (ASCII) form, while X_B stores it in compact binary form. The file extension identifies how the data is stored, not a different modeling kernel. When exchanging a model, select a variant and Parasolid version that the recipient's application can import.
Why is my Parasolid model too large or too small after import?
Parasolid units are always meters. When importing into a CAD program, the units should be scaled accordingly. A mismatch between the file's units and the import settings can make a model appear too large or too small. Check a known dimension after importing, especially when the receiving project uses millimeters.
Why use Parasolid to exchange Designcenter (NX), SolidWorks, and Designcenter Solid Edge models?
Parasolid is not only an exchange format but the modeling kernel of Designcenter (Siemens NX), SolidWorks, and Designcenter Solid Edge. Therefore, X_T and X_B are the preferred choice for exchanging data between these three and other Parasolid-based systems. The receiving application must still support the exported Parasolid version. The shared kernel does not remove the need to agree on a compatible version for the specific exchange.
Can Parasolid files be exchanged between different Parasolid versions?
Yes. Most Parasolid-based CAD systems can export data in older Parasolid versions, and the supported version should be listed in the application's documentation. If a newer file cannot be imported, ask the sender to export a version supported by the recipient. Changing the file name or extension does not change the Parasolid version stored in the file.
Which formats can Parasolid files be converted to?
The 3D-NativeCAD Converter in 3D-Tool Premium reliably converts Parasolid X_T and X_B models to the CAD exchange formats STEP, IGES, JT, and SAT. It also converts them to supported visualization formats such as STL, OBJ, 3DS, PLY, 3D-PDF, 3D-HTML, FBX, 3MF, and glTF. A CAD exchange format is suitable for further CAD processing; a visualization format can be selected for viewing or presentation.