Files with proj file extension are associated with the Interface Builder software from Apple. A proj file stores project.

There are 3 other file types using
the PROJ file extension!

empty icon.proj - Insight II NMR project

empty icon.proj - Poseidon for UML project information file

empty icon.proj - L3DT project

Detailed description

Software that open proj file

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PROJ file extension - Apple NeXT Interface Builder project

What is proj file? How to open proj files?

File type specification:

Various data file type icon Various data file type

proj file icon: proj filetype icon

The proj file extension is related to Interface Builder from Apple.

The proj file contains project. Interface Builder first made its appearance in 1988 as part of NeXTSTEP.

The proj file extension might also be used by other programs for their projects.

The default software associated to open proj file:

Interface Builder icon

Apple, Inc. logoInterface Builder  Apple macOS / Mac OS X software

Company or developer:
Apple, Inc.

Interface Builder is a software development program for Mac OS X (macOs) and part of Xcode. It is an application for designing and testing user interfaces. Developers can use Interface Builder to create user interfaces that follow the Mac OS X (macOS) human-interface guidelines by dragging user-interface elements from a palette of predefined controls and dropping them into the window or view they are configuring.

Help how to open:

Use Interface Builder to work with *.proj files.

How to convert:

As far as we know, this .proj file type can't be converted to any other file format. This is usually the case of system, configuration, temporary, or data files containing data exclusive to only one software and used for its own purposes. Also some proprietary or closed file formats cannot be converted to more common file types in order to protect the intellectual property of the developer, which is for example the case of some DRM-protected multimedia files.

Find conversions from proj file:

proj to mp4

proj to xib

List of software applications associated to the .proj file extension

Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open proj file, edit proj file, convert proj file, view proj file, play proj file etc. (if exist software for corresponding action in's database).

Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting proj files.

Software that open proj file - Apple NeXT Interface Builder project

Programs supporting the exension proj on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about Interface Builder for open proj file action.

Apple macOS / Mac OS X:

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