Opening 4 files

Have a problem opening a .4 file? We collect information about file formats and can explain what 4 files are. Additionally we recommend software suitable for opening or converting such files.

What is the .4 file type?

When used as a true filename extension, the ".4" string belongs to a series of numerical extensions employed by Pro/Engineer to label subsequent versions of its project files. Pro/Engineer is an overwhelmingly complicated and potent piece of CAD (Computer-Aided Design) software that has become an industry standard in many areas that rely extensively on technology.

With Pro/Engineer, a .4 file is a fourth version of the current working project, saved automatically before any changes are committed. Thus, Pro/Engineer allows to keep track of changes and have abundant backup copies at the same time. Versioned Pro/Engineer project files (.4, etc.) are usually saved in one project directory.

Aside from that, the ".4" string in the trailing position of a filename can frequently appear as an extension, while actually being part of the filename. This usually happens on machines running MS Windows with the "Hide extensions for the known file types" option turned on (the default behavior). Besides being a potential security issue, hiding extensions can create confusion around actual file types, so it should be disabled.

In a Unix/Linux environment, the ".4" string of characters also normally appears as part of a filename rather than an extension. Such versioned filenames usually belong to shared library files and symbolic links to those (e.g., "libusb-0.1.so.4" inside the "/lib" directory).

Software to open or convert 4 files

You can open 4 files with the following programs:
VLC media player
VLC media player by VideoLAN
3D-Tool by 3D-Tool GmbH & Co. KG
Notepad++ by Notepad++ Team

Popular formats