How to analyze folder size
Select a local folder, then read its total size, item counts, largest entries, file-type breakdowns, and modified-date summary. The report uses each item's name, size, and last-modified date. It does not open file contents. Tree view, Flat list, and Treemap show the same scan in different layouts.
- Select a folder with Choose folder.
- Watch the scan progress, then read the stat cards and breakdown panels.
- Inspect the folder structure in Tree view, Flat list, or Treemap.
- Search by name or path, set filters, and select Reset filters to clear them.
- Export the filtered results as CSV or JSON, or select New scan for another folder.
How to see where storage is used
The stat cards show total size, files, folders, average file size, most recent change, and inaccessible files. The Largest files and Largest folders lists show up to ten entries each. The By category, Top extensions, Size distribution, and Last modified panels break down the scanned files.
Projects/
├── report.pdf (2.00 MB)
└── assets/
└── logo.png (350 KB)
Total size: 2.34 MB
Largest file: Projects/report.pdf
Categories: Documents, ImagesTreemap gives larger items larger blocks. Select a folder block to drill into it, then use the breadcrumbs to move back up. File blocks are displayed without a drill-down action.
How to check folder size by file type
Known extensions are grouped into Images, Video, Audio, Documents, Archives, Code, and Executables. Files with an unknown or missing extension go into Other. Top extensions lists the ten largest extension groups. Size distribution places files in buckets such as < 10 KB, 10 KB to 100 KB, and > 100 MB.
The Modified filter covers the last 7 days, last 30 days, last year, or older than a year. During a File System Access API scan, a file whose metadata cannot be read appears as inaccessible and has a size of zero in the report.
Search and filter a local folder report
Search checks both name and path. The Type, Category, and Extension controls narrow the matches. Minimum size (KB) and Maximum size (KB) set size bounds. In Flat list, select a column heading to sort by Name, Path, Type, Category, Size, or Modified.
Flat list renders the first 2,000 matching rows and shows the full match count. CSV and JSON export the full filtered list with each item's name, path, type, category, extension, size, and modified date. JSON also includes totalSize and itemCount. Search and filters leave Treemap unchanged.
Examples for a folder report
- Before moving a Projects folder to another drive, check its largest files and subfolders to estimate the transfer contents.
- For a growing Assets folder, filter by Images, Archives, or a size range, then export the matching paths.
- For an old backup, set Modified to Older than a year and review the results in Flat list.
Choose the right file analysis tool
Use Folder Size Analyzer for storage totals and folder hierarchy in the File Management Analyze Tools category. Choose the Duplicate File Finder for byte-identical groups based on content hashes. Choose the File Age & Path-Length Analyzer for age buckets or path-length checks. Choose the File Encoding & Line-Ending Analyzer for text encoding, line-ending, line, and word counts.
Frequently asked questions
How do I analyze folder size in a browser?
Select a folder with Choose folder, wait for the scan, and review the stat cards, lists, and breakdowns. The report uses local file metadata in the browser.
Can I see which file types use the most space?
Yes. The By category and Top extensions panels rank storage by mapped category and extension. The filters can narrow the result to one category or extension.
Does Folder Size Analyzer upload or read my files?
The scan uses each selected item's name, size, and last-modified date. It does not read or upload file contents, and it does not delete, move, rename, hash, compare, or modify files.
Why can't I select a folder?
Folder selection needs the File System Access API or a webkitdirectory directory input. If neither feature is available, the page disables Choose folder and shows an unsupported message.