Native CAD interfaces
Direct support for the CAD formats listed here.
JT Viewer
Open JT files
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affordable & universal many 3D/2D interfaces
Modern, easy-to-use CAD viewer
Cost-effective CAD converter for many formats
The 3D-Tool Viewer opens JT files without any additional CAD software.
The 3D-NativeCAD Converter converts JT models, depending on their geometry, to exchange formats such as STEP, IGES, SAT, and Parasolid X_T or 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.
Opening JT Files From the Automotive Supply Chain
A JT file often comes from the automotive supply chain, for example exported from a PLM system such as Teamcenter, and needs to be opened by suppliers or partners without a Designcenter (Siemens NX) license of their own. The 3D-Tool Viewer opens these JT models directly, showing assembly structure and geometry without the original CAD system.
Free JT readers are usually built for viewing only. 3D-Tool goes further: when the file contains exact geometry (JT-BREP), dimensions can be checked directly, and the 3D-NativeCAD Converter converts the model to formats such as STEP or IGES when needed.
What is the JT file format?
- Files with the JT file extension contain 3D models in the Jupiter Tessellation format. JT was originally a pure visualization format and has since become a complex exchange format for 3D designs. Many newer CAD programs can open and create JT files.
- A current JT file can contain:
- exact geometric data (JT-BREP, X_T-BREP)
- triangulated visualization data (MESH)
- the assembly structure
- materials and colors
- Product Manufacturing Information (PMI)
- The format is continuously evolving. Together with the new STEP AP242, JT is intended to become the standard for 3D data exchange in the future.
JT versions
Unigraphics Solutions developed JT for production use based on customer requirements as early as 1997 (version 6.4). In December 2012, JT was officially published under ISO 14306:2012 as a neutral and license-free 3D visualization format. The basis was JT version 9.5.
Work on a second, extended version of the ISO standard began in 2013. This second version of ISO 14306 was published in 2017.
With the JT Open Toolkit, Siemens PLM provides a free C++ programming interface. It gives users ISO-compliant read/write access to the extensive JT data.
JT assembly variants
JT assemblies are available in several variants:
- monolithic (one file)
- per part/atomic (an assembly file plus a folder of individual part files)
- shattered (one file per node)
- other variants are PLMXML + JT, STEP + JT, or one JT file matching each PRT file from Designcenter (Siemens NX)
How do I open JT files?
Many 3D visualization and design programs can read JT files. If JT files contain exact geometry (BREP), CAD/CAM programs such as Designcenter (Siemens NX) or Designcenter Solid Edge can also read them.
To view a 3D design in JT format, there are free JT readers such as JT2Go from Siemens or some online viewers. The focus here is on the presentation rather than the analysis of the designs.
The 3D-Tool CAD Viewer opens JT files in the supported versions. Professional measurement tools and analyses make use of the JT data.
How can I convert a JT file?
Convert a JT file with a 3D CAD converter, for example from JT to STEP, from JT to STL, or to another 3D format. The file contents are decisive. Only files containing exact 3D geometry (BREP) can be converted to STEP, IGES, or other exact CAD formats. Files containing only visualization data (MESH) can only be converted to visualization formats such as STL or VRML.
The 3D-NativeCAD Converter in 3D-Tool Premium converts many 3D CAD formats, including JT (BREP), to the 3D exchange formats STEP, IGES, SAT, and Parasolid X_T. The 3D-Tool Viewer itself converts JT models (BREP and MESH) to mesh formats such as STL and PLY. The file format comparison shows which 3D-Tool editions and the converter import JT files and which output formats are available.
Without 3D or CAD software with a JT interface, the model must be exported from the original CAD system. The 3D format must be suitable for the target application.
Try the JT viewer and JT 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 JT files for the 3D-Tool Free Viewer or as 3D-PDF
- Open JT files and save them as STL, 3DS, PLY, WRL, or OBJ
- Convert exact JT data (BREP) to STEP, IGES, SAT, and X_T
- Convert JT 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 can a JT file contain?
A current JT file can hold exact geometric data (JT-BREP, X_T-BREP), triangulated visualization data (MESH), assembly structure, materials, colors, and Product Manufacturing Information (PMI). The actual contents depend on how the file was exported. A JT file intended only for visualization may contain mesh data without the exact geometry needed for conversion to other CAD formats.
Which files belong to a JT assembly?
JT assemblies can be created as monolithic (one file), per part/atomic (an assembly file plus a folder of individual part files), shattered (one file per node), PLMXML + JT, STEP + JT, or matching each Designcenter (Siemens NX) PRT file. For variants that reference separate files, share the entire set of files. Supplying only the top-level assembly file may leave the recipient without the associated part geometry.
Can I open and measure JT files without Designcenter (Siemens NX)?
Yes. The 3D-Tool CAD Viewer opens JT files without a Designcenter (Siemens NX) installation and provides measurement and analysis tools. JT files can contain exact CAD geometry, visualization data, or both. The contents of the supplied file determine which geometry is available for inspection and subsequent conversion.
Can every JT file be converted to STEP or IGES?
Only files that contain exact 3D geometry (BREP) can be converted to STEP, IGES, or other exact CAD formats. Files that contain only visualization data (MESH) can only be saved in visualization formats such as STL or VRML. Before converting, clarify whether the sender exported exact geometry or only a lightweight visualization model.
Which JT versions does 3D-Tool open?
The 3D-Tool CAD Viewer opens JT files in the supported versions and provides measurement and analysis tools for inspecting the imported models. The supported version is relevant when receiving files from other applications. The geometry contained in the file also determines whether the model can be converted to exact CAD formats or only to visualization formats.