JkDefrag GUI is a convenient GUI (Graphical User Interface) for JkDefrag, which is a free (GNU GPL) disk defragment and optimize utility for Windows.

JkDefrag is a Free (released under the GNU General Public License) disk defragment and optimize utility for Windows 2000/2003/XP/Vista/X64.

Completely automatic and very easy to use, fast, low overhead, with two optimization strategies, and can handle floppies and USB disks/sticks.