TreeSize 1.51 is a freeware utility. You load TreeSize from your right context mouse menu from within Explorer. Just left click on a directory or a drive ... right click your mouse ... select TreeSize ... and a window will pop up full of useful information. You can quickly see the size of directories and sub directories by bytes or percentage. You can sort the information in a variety of ways. You can see the amount of wasted space on the drive, and you can even print out a report.

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