treemap

WinDirStat is a disk usage statistics viewer and cleanup tool for various versions of Microsoft Windows.

Disk space analysis and reporting tool for Windows

Disk space analyzer with an interactive treemap

Visual disk-space analyzer for Windows with an interactive treemap and safe Recycle Bin cleanup.

Fast local disk space visualization for Windows with cushion treemaps.

Fast, open-source disk space analyzer for Windows

Disk space analyzer that reads the NTFS MFT directly and shows what it is about to delete.