Information about the .par2 (par2) file type

Below is all the information we have available on file about the .par2 (par2) file type.

.par2
RAR archive parity file. Also known as a Parchive or Parity Archive Volume set file.

Files of type .par2 are parity files which sometimes accompany .rar compressed archive files. A .par2 file does not itself contain any compressed data, but contains parity information which can be used to repair a corrupt .rar archive file (or a missing file where the compressed archive is split across several files.

There may be more than one .par2 file for a given RAR archive, and these can be used individually although recovery is then only possible if the appropriate .par2 file is available. It is important to note that it might not be necessary to have all .par2 files available in order to recover a corrupt RAR archive. The following is taken directly from the Parity Volume Specification 2.0:

PAR 2.0 files should always end in ".par2". For example, "file.par2". If a file contains recovery slices, the ".par2" should be preceded by ".volXX-YY" where XX to YY is the range of exponents for the recovery slices. For example, "file.vol20-29.par2". More than 2 digits should be used if necessary. Any exponents that contain fewer digits than the largest exponent should be preceded by zeros so that all filenames have the same length. For example, "file.vol075-149.par2". Exponents should start at 0 and go upwards.

cf .par, .p01, .p02.

The following links provide further information related to the .par2 file extension:

Where this is available we would like to include file format information on .par2 files, as well as information on how to view or open files of type .par2. If you know of any information which we have missed then please let us know.