In computing, fc (File Compare) is a command-line program in DOS, IBM OS/2 and Microsoft Windows operating systems, that compares multiple files and outputs the differences between them.

[2][3] It is similar to the Unix commands comm, cmp and diff.

The fc command has been included in Microsoft operating systems since MS-DOS 2.11 (e.g. on the 1984/85 DEC Rainbow release)[4] and is included in all versions of Microsoft Windows.

[6] DR DOS 6.0 includes an implementation of the fc command.

The output of fc is intended primarily to be human readable and may be difficult to use in other programs.