For years, Windows users have checked their disk space through File Explorer and the good ol' Computer (or "My PC" in Windows 8.1) interface on the desktop. But that only tells you how much total space is left on your drive. To figure out which file types or folders were taking up all that space, you had to dive into your file system.
In Windows 8.1, Microsoft offers two features in the modern UI PC Settings app that make managing your disk space much easier.
Fire up the PC Settings app by opening the Charm bar, selecting Settings, then Change PC settings.
With the PC Settings app open, navigate to PC and devices > Disk space and then wait. Depending on how many files you have it could take a while before you see any results. Just let the app think and do its magic.
Once it's done, you should see a summary of how much available disk space you have at the top of the screen, followed a quick tally of how much space your Modern UI apps are taking up (we'll get to that later), and then a summary of exactly where all the space on your drive is going.
Keep in mind that these summaries are organized by the specific named folders—Documents, Downloads, etc.—and not the Windows libraries that bring together similar file types saved in different locations across your PCs.
The important part of this summary is that it shows how much disk space each folder is taking up. So if you find that your Pictures folder is taking up all your PC's disk space, it might be time to consider offloading some of those images to an external drive or uploading them to cloud storage.
Another nice feature of this page is that it includes the ability to empty the recycle bin. The disk space feature is a new addition to Windows 8.1 via the recent spring update.
Up towards the top of the disk space summary you'll see a clickable link called See my applications' sizes. Clicking that link will take you to Search and apps > App sizes inside the PC Settings app, a feature that first appeared with Windows 8.1.
What you'll see when you get there is a list of all your modern UI apps and how much space each takes up. The Modern UI Start screen doesn't show this information. If you'd like to uninstall some of the larger ones, just tap or click the app and select the Uninstall button.
If you don't want to uninstall modern UI apps one at a time try out Windows 8 App Remover for bulk uninstalling.
Thanks to Windows 8.1 and the PC Settings app, figuring out which files and apps are taking up all your disk space just got a little bit easier.