Filelight is an open source disk space analyzer for Linux and Windows

What do you do when you're running low on storage space? I run disk cleanup to clear the updates and system files, purge the browser data, and if that doesn't help I use a program like SpaceSniffer or WizTree.

That's on Windows of course. For a cross-platform solution, you can use something like Filelight; this is a KDE application that was officially ported to Windows. The start screen of Filelight displays a circle for each hard drive and partition. The colored part of the ring shows the used space and the white areas indicates the free space on the drive. Mouse over the colors to view the storage information in Gigabytes.

Clicking on one of the rings initiates a scan of the selected drive. A nice pie animation is displayed that also acts as the progress indicator.

Hit the stop button on the toolbar to cancel the scanning process. You can also analyze the storage space used by a folder (and it's sub-folders) by using the open button on the toolbar or the Scan menu option. A third way to run a scan is by using the address bar at the top of the screen.

The time taken for the scan to complete depends on various factors such as the total storage capacity of the drive, the amount of used space, and also the drive's read speed. When the scan completes you will see a set of colorful concentric rings; this is the file map. Each color represents various folders, while the gray represent files.

Hovering over a ring (segment) displays the name of the folder that it represents and the total disk size of that directory. Moving the cursor away from a folder (inner ring) to the outer ones shows the details about sub-folders that it contains. This way, you can quickly find out what's taking up a lot of storage space.

Click any folder or sub-folder to view its own set of rings. Use the back/forward or up buttons (also available from the Go menu) to navigate between the views. Optionally, you can use the Zoom In and Out options under the View menu for  increasing/decreasing the view. The rescan option may be useful when you move something to a different directory, and wish to view the results of the current storage space.

Context menu

Right-click on a folder ring to open it in the File Manager/Explorer, or to open a command window in the selected location. Left click on a file to open it in its default handler program. That's useful in case you want to preview it, before you decide to delete it to recover some storage space.

The Settings > configure Filelight menu can be used to access the program's settings. The "Scanning" tab lets you exclude folders that you don't want to be scanned. The "Appearance" tab can be used to customize the font size and to change the color scheme of the application.

Personally, I like the Rainbow theme but if you prefer something light or dark, use the High Contrast theme or System colors. Anti-aliasing is enabled by default, but can be toggled if you want the jagged-edge look.

Filelight is available in a standalone version like all KDE's programs on the Binary Factory portal. It's also available on the Windows Store, should you want that. The versions are identical, except for the fact that the Store version is behind on updates.

(Windows Store version on the left, installer version to the right)

Linux users can install it via the KDE Discover software manager. If you don't have it, just run the following command in the terminal:

sudo apt install plasma-discover

You can then install Filelight or other KDE apps on your distro.

Filelight isn't as fast as WizTree, but it offers a better visual representation of the used storage space, and in that sense a lot more user-friendly.