Author: Joachim Eibl

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, autodetection via byte-order-mark "BOM"

supports KIO on KDE (allows accessing ftp, sftp, fish, smb etc.),

Printing of differences,

Manual alignment of lines,

Automatic merging of version control history ($Log$),

and has an intuitive graphical user interface.

Windows-Explorer integration Diff-Ext-for-KDiff3 - shell extension included in installer (originally by Sergey Zorin: see also Diff Ext)

KDE-Konqueror/Dolphin service menu plugin

Simplified integration with IBM-Rational-Clearcase for Windows (Details).

Read what else is special in a short abstract (PDF).

KDE4

Any Un*x that is supported by the Qt-libs from qt-project.org,

MS-Windows.

Apple Mac OSX binary available. (0.9.98)

In theory any platform for which Qt-libs work (Qt4 or Qt5).

Interface: az, bg, br, ca, cs, cy, da, de, el, en, en_GB, es, et, fr, ga, gl, hi, hu, is, it, ja, ka, lt, nb, nl, pl, pt, pt_BR, ro, ru, rw, sr, sr@Latn, sv, ta, tg, tr, uk, zh_CN

Documentation: en

Documentation (PDF): en, da, de, es, et, fr, it, nl, pt, sv,

Installation:

tar xvfz filename.tar.gz

and follow the instructions in the README-file.