Disk Usage Analyzer

Disk Usage Analyzer is the GNOME utility for working out where disk space has gone. On opening it lists the home folder and the mounted devices it can see, each with its total and remaining capacity, and a scan can be started on any of them or on an arbitrary folder picked from the file chooser.

A scan walks the directory tree and reports the outcome two ways at once: a sortable list of folders with their sizes and item counts, and a graphical view of the same tree drawn either as concentric rings or as a treemap of nested rectangles. Clicking a segment descends into that folder, so the largest consumers can be followed downwards without typing a path.

From the results a folder can be opened in the file manager or moved to the trash directly. Scanning a large tree takes time and reads a great many directory entries, and the figures describe the space the files occupy on disk, which does not always match the sum of their nominal sizes.