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KDIFF3(1) General Commands Manual KDIFF3(1)


KDiff3 — compares two or three input files or directories


KDiff3 [QT options] [KDE options] [KDiff3 options] [File1/base] [File2] [File3]


This manual page documents briefly the KDiff3 tool.

This manual page was written for the Debian distribution because the original program does not have a manual page. For comprehensive help, please see khelpcenter help:/kdiff3.

KDiff3 is a program that

compares or merges two or three text input files or directories
shows the differences line by line and character by character
provides an automatic merge-facility and
an integrated editor for comfortable solving of merge-conflicts
supports Unicode, UTF-8 and other codecs
supports KIO on KDE (allows accessing ftp, sftp, fish, smb etc.)
Printing of differences
Manual alignment of lines
Automatic merging of version control history ($Log$)


This program follows the usual GNU command line syntax, with long options starting with two dashes (`-'). A summary of options is included below. For a full summary of options, run KDiff3 --help.

-m, --merge
Merge the input.
-b, --base file
Explicit base file. For compatibility with certain tools.
-o, --output file
Output file. Implies -m. E.g.: -o newfile.txt
--out file
Output file, again. (For compatibility with certain tools.)
No GUI if all conflicts are auto-solvable. (Needs -o file)
Don't solve conflicts automatically. (For compatibility...)
-L1 alias
Visible name replacement for first file/base file.
-L2 alias
Visible name replacement for second file.
-L3 alias
Visible name replacement for third file.
-L, --fname alias
Visible name replacement. May by supplied for each input.
--cs string
Change a setting, e. g. --cs "AutoAdvance=1".
Show a list of all settings and their values.
--config file
Use a different settings file.
Show author of program.
-v, --version
Show version of program.
Show license of program.


This manual page was written by Eike Sauer <> for the Debian system (but may be used by others). Permission is granted to copy, distribute and/or modify this document under the terms of the GNU General Public License, Version 2 (or, at your option, any later version published by the Free Software Foundation).

On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL.