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Siemens NX Viewer
open and convert NX and I-Deas files

CATIA Siemens-NX CREO SolidWorks Solid Edge Autodesk Rhino JT STEP X_T DWG-DXF-DWF DGN-IFC PDF-PRC-U3D IGES-SAT-VDA DAE-FBX-glTF 3MF-STL PLY-3DS-WRL-OBJ

Was are PRT files?

  • The file extension PRT is used by several programs. In the CAD/CAM area, these are native 3D models from either Siemens NX or Creo. Creo files can often be recognized by a number after the file extension (*.prt.1, *.prt.2).
  • PRT files from Siemens NX can contain 3D components, 3D assemblies, 2D drawings and product manufacturing information (PMI).
  • One Siemens NX assembly file is linked to at least one but usually more than one PRT part and often also to other PRT assemblies.
  • UGS developed the two CAD systems Unigraphics NX and I-Deas in 1978 and 1982 respectively. UGS was acquired by Siemens in 2007, and Siemens combined the two systems to create today's Siemens NX.

Siemens NX viewer for PRT part and assemblies

PRT File Versions

New releases of Siemens NX are published regularly. Newer releases have the version scheme 2206, 2212, 2306, whereby 2306, for example, stands for June 2023. The current version is 2412. (06/2025)

Older releases from 2019 to 2021 have the designations NX 1847 to NX 2007. Prior to that, they were simply version numbers NX to NX 12. Until 2001, the designations were UG/Unigraphics 3.0 to 18.0.

As of 2013 or NX 9, Siemens PLM Software only offers the software as a 64-bit version. The MacOS support has been discontinued with NX 12.

I-Deas and its file formats MF1, ARC, UNV, and PKG are still in use, but primarily for maintaining existing long-term projects and historical data, particularly in the automotive, aerospace, and defense industries.

Additional Native Siemens NX File Formats

In contrast to most other CAD systems, NX has no individual file extensions for parts, assemblies and drawings.

Worth mentioning is the Parasolid modeling kernel used by Siemens NX. Parasolid X_T and X_B files are 3D exchange formats without a modification history, but are the first choice for exchanging 3D models between CAD/CAM programs with a Parasolid core such as Siemens NX, SolidWorks and Solid Edge.

The native I-Deas formats MF1, ARC, UNV, and PKG are only partially supported by Siemens NX and require special import and conversion interfaces.

How do I Open Siemens NX and I-Deas files?

For native Siemens NX PRT data, a Siemens NX installation is typically used. Opening the files with CAD/CAM software that has a Siemens NX interface is also possible. For example, PRT files can be opened in SolidWorks and Solid Edge.

Without an I-Deas installation, the native I-Deas formats MF1, ARC, UNV, and PKG generally require special import and conversion interfaces.

Although there are no free NX and I-Deas viewers available, CAD viewers are an affordable alternative compared to a full CAD system. The 3D-Tool CAD viewer opens all of the Siemens NX and I-Deas file formats listed above and can be tested free of charge for 14 days.

How do I convert Siemens NX and I-Deas files?

If you don't have CAD software with a Siemens NX or I-Deas interface, the design must be exported to a common 3D exchange format, such as STEP.

Converting Siemens NX and I-Deas to STEP is also possible with a 3D converter or CAD converter. 3D-Tool Premium includes the 3D NativeCAD Converter. In addition to native Siemens NX models, this converts I-Deas models and models from many common CAD systems into the 3D exchange formats STEP, IGES, SAT, and Parasolid X_T, which are supported by most CAD/CAM programs.

Test the Siemens NX Viewer and Siemens NX Converter

3D-Tool is a CAD viewer with many native CAD interfaces, including Siemens NX and I-Deas. 3D-Tool offers professional measurement, draft analysis, and wall thickness analysis.

  • Open, dimension, annotate, and publish Siemens NX and I-Deas files for the 3D-Tool Free Viewer or as 3D PDF
  • Open Siemens NX and I-Deas files and save them as STL, 3DS, PLY, WRL, OBJ, or PLY
  • Convert Siemens NX and I-Deas files to STEP, IGES, SAT, X_T, and JT
  • Convert NX and I-Deas models into 3D product visualizations such as 3D HTML, FBX, Collada, 3MF, and glTF.

Free and non-binding 14-day trial with all features, the Siemens NX interfaces, and the 3D Native CAD Converter. The demo key activates all 3D interfaces, such as CATIA, Siemens NX, SolidWorks, Inventor, STEP, SAT, and Parasolid.

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