A daily updated filename extension database!

PROJ file extension

The table below provides useful information about the .proj file extension. It answers questions such as:

  • What is the .proj file?
  • What program do I need to open a .proj file?
  • How can the .proj file be opened, edited or printed?
  • How can I convert .proj files to another format?

We hope you find this page helpful and a valuable resource!

1 extension(s) and 0 alias(es) found in database

✅ Poseidon for UML Project Information

PROJ file is a Poseidon for UML Project Information. Poseidon for UML is a software application used to create models with the Unified Modeling Language.
Category: Data files
Application: Poseidon for UML
Mime-type: application/octet-stream
Magic number: -
Magic string: -
Sample: -
PROJ aliases:
PROJ related links:
PROJ related extensions:
Poseidon for UML Project

Other types of files may also use the .proj file extension.

🚫 The .proj file extension is often given incorrectly!

According to the searches on our site, these misspellings were the most common in the past year:

prj, pro

Is it possible that the filename extension is misspelled?

We found the following similar file extensions in our database:

Infinity Engine Projectiles Data
KiCad Project File
Carlson 2016 Profile Data
FEMFAT Result Protocol Data
ALEID2000 Project
AquaCrop Single Project
Carlson 2015 Profile Data
PATCHMASTER Protocol Editor Information
General Project File
Steinberg WaveLab Workspace

🔴 Can't open a .proj file?

When you double-click a file to open it, Windows examines the filename extension. If Windows recognizes the filename extension, it opens the file in the program that is associated with that filename extension. When Windows does not recognize a filename extension, you receive the following message:

Windows cannot open this file:


To open this file, Windows needs to know what program you want to use to open it...

If you don't know how to set the .proj file association, check the FAQ.

🔴 Can I change the extension of files?

Changing the filename extension of a file is not a good idea. When you change a file's extension, you change the way programs on your computer read the file. The problem is, changing the file extension does not change the file format.

If you have helpful information about the .proj file extension, write to us!

Browser: Abbreviation Application Archive Audio Configuration Data Development Disk Image Document Ebook Font Game Data GIS Graphic Malware Multimedia Other Project Scam Unknown Video
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