O File - opening and understanding

Did your computer fail to open an O file? We explain what they are used for and recommend software that we know can open or otherwise handle your .O files.

What is an O file?

The .o file extension is most commonly used for compiled object files. These files are created by C compiler applications. They are usually created during the program development process and are used in place of the common program file. These files are used for a variety of platform programs including Unix and Free Pascal.

The .o file extension is also used for Atari Jaguar object module pre-linked compiled code files and Atari Jaguar 68000/mixed object module files.

How to open O files

You will need a program compatible with the specific file you are trying to open, as different programs may use files with file extension O for different purposes.

While we have not verified the apps ourselves yet, our users have suggested 4 different O openers which you will find listed below.

Suggest another file format using extension O

While we know of one file format using the .O file extension, there may be more. It is widespread that different programs use files with the same file extension for very different types of data. Please let us know if you are aware of a different kind of .O file.

Various viewers for this file format

These apps are known to open certain types of O files. Remember, different programs may use O files for different purposes, so you may need to try out a few of them to be able to open your specific file.

PIC-C CompilerPIC-C CompilerUser submitted
Microsoft OfficeMicrosoft OfficeUser submitted
QUINCY ApplicationQUINCY ApplicationUser submitted
OEditOEditUser submitted
We have not verified any software that we know for certain will work with O-files on Mac. If you know one, please use the 'Suggest a program' link below and tell us about it!
We have not verified any web services that we know for certain will work with O-files. If you know one, please use the 'Suggest a program' link below and tell us about it!