PRJ Converter

PRJ to STL, OBJ, STEP and more. reaConverter processes 3D files for easy sharing across different platforms.

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PRJ Files
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PRJConverter

How to Convert .prj Files in Bulk

1. Install reaConverter

Download reliable PRJ conversion software to convert multiple .prj files and folders in one go.
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Install reaConverter

2. Select PRJ Files

Select PRJs from a folder or drag and drop them into reaConverter, then choose the desired output format.
reaConverter - Load PRJ files

3. Start Conversion

Click Convert to start the bulk conversion of all selected PRJ files. The process will begin right away.
reaConverter - Start PRJ conversion

Convert PRJ on your PC

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.

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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.

Conversion features
Image editing

User Reviews

Average User Rating:
Last updated on November 27, 2025
"reaConverter's automation tools have completely changed how I manage my projects. I often work with large batches of illustrations and used to spend hours converting and organizing them. Now, with Watch Folders, I just set the rules once and everything is handled automatically, exactly how I need it. This is pro-level automation made simple."
Chloe M.
Chloe M.
Freelance Illustrator
"We receive artwork in all kinds of formats from clients. reaConverter takes care of converting them all to print-ready specs automatically using Watch Folders. It reduces errors, saves us time, and has improved our turnaround time with customers. Incredibly powerful software."
Michael D.
Michael D.
Print Shop Owner
"The step-by-step video makes conversion foolproof. I'd recommend this to my grandma - it's that well-explained!"
DeShawn M. Thompson
DeShawn M. Thompson
Happy User
"5/5⭐ Finally! Does what it promises - converts AND tweaks images without complicated menus. Perfect for quick jobs."
J. Mitchell
J. Mitchell
Satisfied Customer
"This software just works! My old laptop can’t handle Photoshop, but reaConverter flies through conversions without breaking a sweat. Wi-Fi gone? Still strong!"
Robert Williams
Robert Williams
Happy User
"After 200+ conversions on my budget laptop (i3-1115G4/4GB RAM/Win11), reaConverter outperforms heavyweight tools. Zero crashes, low CPU usage during batch processing, and no internet dependency - exactly what professionals need."
Walter Morgan
Walter Morgan
Satisfied Customer

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 DICOM filesResize pictureConvert PDF filesWatermark imagesConvert vector files

What formats can I convert a PRJ file to?
ai  apng  avif  bmp  bpg  cal  cg4  cgm  cin  dcx  dds  dgn  dis  drw  dwf  dwg  dxf  emf  epi  eps  fax  fits  flif  gbr  gif  glb  gltf  hpg  hru  ico  iff  iges  igs  jp2  jpeg  jpg  jxl  jxr  mif  mtv  pcl  pct  pcx  pdf  pgm  pic  plt  png  ppm  prc  ps  psd  qoi  qrt  rad  rla  sgi  shp  step  stl  stp  svg  svgz  tga  tif  tiff  webp  webpll  wmf  wmz  wpg  wrl  x3d  xbm  xpm 

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Explore our efficient PRJ file converter that saves you time and effort by converting multiple .prj files into different formats.
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