GDU is a free and open-source tool for PC made by indie developer dundee aka Daniel Milde. Its name stands for Go Disk Usage and is a disk usage analyzer utility that was written in the Go programming language. It is terminal-based so you'll need your command prompt to run it.

Similar to TreeSize and Disk Space Fan, GDU lets users analyze and determine data usage on their various storage devices. What makes this portable tool different is the fact that there's no graphical user interface and is used through a command terminal. It's lightweight and runs much faster, though, as a result.

How do I use GDU?

To start scanning a drive, just type GDU  e.g. GDU C: and press enter. The scan will only take a few seconds to complete, and it will display a breakdown of your disk usage immediately. It also features a colorized command window to make it easier to distinguish between files and folders. There's also an option to display results in monochrome by typing in GDU -c  to enable it.

The bottom bar shows total disk usage and the number of items contained. To set a path, type GDU  or GDU C:\Users\Softonic\Documents\, using the arrow keys for navigation. Use hotkeys for various file operations. Press Enter to open a folder or H to go back. Sort by name or size with the N and S keys respectively. Open text files with V, and Escape to close after. For deletions, you use the D key.

Lastly, you can export the data to a text file, type in GDU > .txt C:\ to generate one. When you're done, just press Q to close the tool. There will be a slight learning curve in the beginning, but you can always press the ? key to see the list of all available commands for reference.

Fast and straightforward

Using GDU will be a little intimidating at first, especially if you're not used to operating the command terminal. Once you get the hang of it, though, you will appreciate the speed and simplicity that this tool affords you. If you're for a lightweight tool to analyze your disk usage, give this one a go.