Use one of these tools to figure out why your hard drive, flash drive, or external drive is filling up. Some of them even let you remove files directly from the program. You can analyze internal and external hard drives, search through the results, delete files from within the program, and group files by extension to see which file types use the most storage. You can also examine a list of the top 100 biggest files or folders and export the list to your computer to review later. There’s a professional version available, too, but the freeware edition seems perfect. Install it on Windows 11 through Windows XP, as well as on Windows Server 2022–2003. Create your own custom cleanup commands to do things quickly, like moving files off the hard drive or deleting files of a certain extension in a selected folder. You can also scan different hard drives and folders at the same time, as well as see which file types use the most space. You can install WinDirStat only in the Windows operating system. Windows 95, Windows 98 SE, Windows ME, Windows NT4, etc., up through Windows 11 should work. In the left pane, you’ll find the folders that were scanned, while the right pane displays ways to analyze that data. You can’t delete files from within the program, and the time it takes to scan a hard drive seems slower than some other applications in this list. Windows, Linux, and Mac users can use JDiskReport. If you find folders or files that you no longer want, delete them from within the program to free up that space. Get a portable version that runs on external hard drives and flash drives without installing it to the computer. Only Windows can run TreeSize Free. Scan a single folder with RidNacs or scan whole hard drives. This is an important feature in a disk analyzer program because scanning an entire hard drive may take a long time when you really just need to see the info for one folder. Open the folders as you would in File Explorer to see the folders or files listed in descending order. RidNacs includes the basic features necessary for what a disk analyzer should have, but it lacks the features you’d find in a more advanced program such as WinDirStat. Each time Disktective opens, it asks what directory you want to scan. You can choose any folder on any hard drive that’s plugged in, including removable ones, as well as the entire hard drives. The left panel of the program shows the folder and file sizes in a familiar File Explorer-like display, while the right side displays a pie chart for visualizing each folder’s disk usage. Disktective is relatively user-friendly, but it’s hindered by a few key limitations: the export-to-HTML feature doesn’t produce a very easy-to-read file, you can’t delete or open folders or files from within the program, and the size units are static, meaning they’re all either in bytes, kilobytes, or megabytes (whatever you choose). Right-clicking any folder or file in SpaceSniffer opens the same menu that you see in File Explorer, meaning you can copy, delete, and perform other file functions. The filter feature lets you search through the results by file type, size, or date. You can export the results to a TXT file or a SpaceSniffer Snapshot file. In the Folder Size settings, you can disable CD and DVD drives, removable storage, or network shares. The Folder Size interface is nothing like the other analyzers in this list. If you don’t need charts, filters, and advanced features, and only want to sort folders by size, this program will do just fine.