CSO File - opening and understanding

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

What is a CSO file?

Files that contain the .cso file extension are compressed image files that are most commonly used to archive games that have been designed for use on the Playstation PSP portable gaming system. The CSO file format was the first compression method used for ISO file purposes.

The CSO files are saved in an ISO disk image format and they may contain up to nine levels of compression. It is important to note that the more compression that a CSO file has, the longer it will take for the disk image to load. This can have a significant impact on the user's gameplay or computing experience.

How to open CSO 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 CSO for different purposes.

While we have not verified the apps ourselves yet, our users have suggested 3 different CSO openers which you will find listed below.

Suggest another file format using extension CSO

While we know of one file format using the .CSO 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 .CSO file.

Various viewers for this file format

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

WinRARWinRARUser submitted
uTorrentuTorrentUser submitted
DAEMON Tools LiteDAEMON Tools LiteUser submitted
We have not verified any software that we know for certain will work with CSO-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 CSO-files. If you know one, please use the 'Suggest a program' link below and tell us about it!