Par2cmdline is a command line utility for creating and using PAR2 files to detect and repair damage in data files. It is most commonly used as part of backup systems as well as on Usenet.

In case files in a recovery set get damaged (e.g. while transmitted over a network or stored on a faulty disk) the program can read the damaged files and the (possibly damaged) PAR2 files, and regenerate the original input files.