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 all formats
The 3D-Tool Viewer opens JT files without any additional CAD software.
The 3D-NativeCAD Converter converts JT models to a wide range of formats such as STEP, IGES, SAT, Parasolid X_T, STL, OBJ, 3DS, PLY, 3D-PDF, 3D-HTML, FBX, 3MF, and glTF.
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Windows support
Compatible with current Windows versions.
What are JT files?
- Files with the JT file extension contain 3D models in the Jupiter Tessellation format. Originally a pure visualization format, JT has 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), assembly structure, materials, colors, and Product Manufacturing Information (PMI).
- The format is continuously evolving and, together with the new STEP AP242, is intended to become the standard for 3D data exchange in the future.
JT versions
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. It has been developed by Unigraphics Solutions since 1997 (version 6.4) for productive use on the basis of customer requirements.
In 2013, a second, extended version of the ISO standard was implemented and the international industry standard ISO/DIS 14506 V2 was officially published in 2017.
With the JT Open Toolkit, Siemens PLM provides a free C++ programming interface with which users have ISO-compliant read/write access to the extensive JT data. The current version is 10.10. (05/2026)
JT assembly variants
JT assemblies can be created in different variants:
- monolithic creates a single file with all assemblies and parts.
- per part (atomic) creates an assembly file and a folder of the same name containing all parts as individual files.
- shattered creates a file for every node, meaning every assembly, subassembly, part, and component.
- PLMXML + JT creates an XML assembly file and a separate JT file for each part.
- STEP + JT creates a STEP AP242 assembly file and a separate JT file for each part.
- same as Siemens NX (Siemens NX option) creates a corresponding JT file for every Siemens NX PRT, whether assembly or part.
How do I open JT files?
JT files can be read by many 3D visualization and design programs. New JT versions with exact geometries (BREP) can also be used by CAD/CAM software such as Siemens NX or Solid Edge.
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 from version 8.0. Professional measuring tools and analyses utilize the full potential of JT data.
How can I convert a JT file?
Without 3D or CAD software with a JT interface, the model must be exported from the original CAD system to a 3D format supported by your application.
Converting JT to STEP, JT to STL or to another 3D format is also possible with a 3D converter. However, only files that contain exact 3D geometries (BREPs) can be converted to STEP, IGES or other exact CAD formats. Files that only contain visualization data (MESH) can only be saved in visualization formats such as STL or VRML.
The 3D-NativeCAD Converter in 3D-Tool Premium converts many 3D CAD formats including JT (BREP) reliably into the standard 3D exchange formats STEP, IGES, SAT, and Parasolid X_T. The 3D-Tool Viewer also converts JT models (BREP and MESH) into Mesh formats.
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, VDA, SAT, and X_T
- Convert JT 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 JT, STEP, IGES, SAT, Parasolid, as well as CATIA, Siemens NX, Inventor, SolidWorks, and many other formats.
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