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PRJ Converter
PRJ to STL, OBJ, STEP, IGES and more. reaConverter processes 3D files for sharing across different platforms.
How to Convert .prj Files in Bulk
1. Install reaConverter
2. Select PRJ Files
3. Start Conversion
Step by step
See It in Action
For quick and effortless PRJ file handling on your PC, reaConverter offers powerful conversion tools with batch processing. Best of all, it works entirely offline — ensuring your sensitive data never leaves your computer.
Extra Tools
Do more with your files
Converting PRJ files for use in a larger project? reaConverter offers many ways to process files, so you can customize them according to your requirements.
Our range of editing options includes auto-processing options such as auto-rotate, auto-crop, watermarking and more. Change Color Space, copy Metadata, set DPI, manage ICC Profile, control Bit Depth.
User reviews
From those who tried it
Average User Rating:Last updated on June 29, 2026
Questions & Answers
PRJ files: Frequently Asked Questions
What are PRJ files?
The PRJ extension is attached to project files created with 3D Studio, the predecessor of 3ds Max, created for operation on the DOS platform. PRJ is also known as a mesh file, containing graphical data related to geometry, texture, lighting and other relevant info associated to a 3D model.
Can reaConverter open PRJ files?
reaConverter fully supports the PRJ file format – open, edit, and export PRJ files to any other popular file format with ease.
How do I change PRJ to another format?
reaConverter is a user-friendly tool for converting PRJ files. Once installed on your computer, it allows you to convert all your .prj files at once with just a few clicks. You can even convert prj images directly from Windows Explorer using the right-click menu — fast and convenient.
Can I convert PRJ online?
If you only want to convert a few PRJ files, you are welcome to try our free online PRJ converter.
How can I turn PRJ files on my computer to another format?
The best way to convert PRJ files on your PC is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch files conversions, including conversion from PRJ.
How can I automate PRJ files conversion?
reaConverter supports all the essential automation features, such as right-click сonversion and Watch Folders, for the most efficient automated file conversion in any software of its kind.
Can I convert PRJ files using scripts or the command-line interface?
reaConverter provides full access to all its features from the Windows command-line shell, including the command-line prj converter.
What else can I do with reaConverter?
Convert Gerber filesConvert picture color spaceConvert DICOM filesCrop picturesConvert vector files
What formats can I convert a PRJ file to?
Discover More
Beyond PRJ conversion
Convert .prj files in batches of any size, with editing and processing applied along the way. The same tool also handles 700+ other formats, including CAD, medical imaging, and GIS.
