JDiskReport is a free Java-based tool that displays the size, capacity, free space, and other parameters of your files, folders, and directories. You can display data in different views and rapidly switch between them. To use it, you must have an up-to-date version of Java installed, but of course that's free.
JDiskReport starts by scanning either a selected tree directory or your C drive; we chose the latter. We could save and reopen scans, too. JDiskReport displays a folder tree view in the left-hand panel and five tabs in the main window: Size, Top 50, Size Distribution, Modified, and Types. Some displayed pie charts and others bar graphs, but each offered a series of icons along the bottom of the main window for switching between several chart, graph, and list styles, except the Top 50 list view, which switches between Largest, Oldest, and Newest. All the views are useful; under Types, we learned our system had more .dlls than any other file type; 11.5GB of them. We could change the views from file size to numbers, sort by size and name, and copy the table to the clipboard from the View menu. The Options include Look & Feel, Filters, and Commands.
We had some issues when installing and running JDiskReport in 64-bit Windows 7, which seemed to be related to the location of the Java file; an issue that persisted when reopening the program. We were also unable to open JDiskReport from inside Windows shell context menus. Although the program showed up in context menus, clicking the entry produced an Application Not Found error message. The documentation makes no mention of an issue with 64-bit systems, so it may be a Java-related issue. At any rate, the difficulties we experienced with what should have been a very simple tool leave us in a quandary. On the one hand, we really like JDiskReport's data displays. On the other hand, we can't very well recommend software that might give significant numbers of users some headaches. Perhaps one of JDiskReport's frequent updates will answer our concerns.