FREE DISK ANALYZERS
WinDirStat is a free, open-source tool for analyzing directory sizes, named from the combination of 'Windows Directory Statistics'. It is published under the GNU General Public License (version 2).
FolderSizes is a free disk space analysis and reporting tool from Key Metric Software, built in secure software development.
While both WinDirStat and FolderSizes serve the purpose of analyzing disk space usage, FolderSizes provides additional features, enhanced performance, and more robust functionality.
PERFORMANCE COMPARISON
FolderSizes significantly outperforms WinDirStat in both analysis speed and user interface responsiveness.
On a local solid-state drive with 1.5 million files and 309,000 folders, WinDirStat took nearly 3.5 minutes to complete the analysis, while FolderSizes finished in under 20 seconds.
Next, we analyzed a mechanical hard drive containing 1.6m files and 23k folders. The results were similar, with WinDirStat performing the analysis in just over 4 1/2 minutes and FolderSizes finishing in just under 25 seconds.
The performance disparity was even more significant when analyzing remote (network) file systems. Analyzing a network share containing 278k files and 64k folders took WinDirStat just over 9 minutes. FolderSizes completed the same analysis in under 30 seconds.
The WinDirStat user interface became unresponsive frequently during our tests, especially when displaying analysis results.
FEATURE COMPARISON
FolderSizes offers a rich feature set, developed through years of continuous updates, far surpassing the capabilities of WinDirStat. A partial list of FolderSizes features includes:
- Scan filtering
- Export reports to HTML, Excel, PDF, and CSV
- File system snapshots
- Trend analysis
- Built-in scheduling
- Email integration for report delivery
- File and folder metadata search
- Largest, oldest, and newest file reports
- Temporary and duplicate file reports
- File type, attribute, and owner reports
- File size, name, age, and depth reports
- Various themes, including dark mode
- An advanced command-line interface
- And more
ACCURACY
FolderSizes is far more accurate than other file system analysis tools due to its deep understanding of NTFS file system structures.
Accuracy here refers to how well the software reflects the true state of the file system. This is absolutely critical when making decisions about which files to delete or move to free up disk space.
The screenshots below offer a real-world example of how the accuracy of these tools differs. FolderSizes shows the Windows folder of this operating system drive as containing 330,988 files for a total folder size of 38.3 GB.
If we compare this to the size metrics reported by Windows, we see that they match.
However, WinDirStat reports that this same Windows folder contains 324,762 for a total size of 35.3 GB. In this instance, WinDirStat is not "seeing" thousands of files present in this folder - even though they clearly exist, as reported by both Windows and FolderSizes.
Although WinDirStat consistently produced correct results for simple file system structures, scenarios where WinDirStat results were inaccurate and misleading are not uncommon.
SECURITY & TRUST
Security is a cornerstone of FolderSizes, with every release adhering to rigorous best practices.
FolderSizes is developed and published by Key Metric Software, operating entirely within Michigan, USA, since its inception in 2003. The FolderSizes product installer carries a signed validation certificate, making it easy to verify its origin.
Each FolderSizes release undergoes extensive testing for conformance to best software development security practices and is always verifiably free of malware. Our developers engage in continuous monitoring of emerging security vulnerabilities.
RELEASE HISTORY
The last stable release of WinDirStat was in 2007, over 14 years ago, according to Wikipedia.
FolderSizes has undergone hundreds of product releases since its initial release in 2003 and supports all modern Windows operating systems.
CONCLUSION
We encourage you to try both tools and experience the difference for yourself. Download FolderSizes today to see how it can optimize your disk space usage more efficiently and accurately.