PerfectDisk is a defragmentation software product for Windows developed by Raxco.
[1] The application keeps track of file usage to lessen defragmentation time[2] and offers two modes of basic defragging: "quick" and "SmartPlacement".
[3] SmartPlacement was Raxco's proprietary toolkit for more accurate, albeit slower defragging, and was marketed as a main selling point over the built-in tool of Windows' built in defragmentation tools.
As Raxco filled for bankruptcy in April, 2024, PerfectDisk users can still use the installed software, but no activations will be done after May, 2024, and no support will be provided past this date.
The standard Windows "Disk Defragmenter" is based on a subset of a competing, now-discontinued product named Diskeeper.