Disk space analyzer for Windows.
Diskplot scans a drive or a folder and shows what is using the space, as a treemap and a sortable tree in one window.
Free and open source, MIT license. Windows 10 and 11. No account, no telemetry.
Treemap and tree in one window.
The treemap shows proportions at a glance. The tree gives exact sizes, file counts and dates, sortable by any column. Selection is shared: pick an item in one view and it is highlighted in the other.
Features
Live view
The treemap and the tree fill in while the scan runs. There is no waiting for a progress bar to finish.
Scan comparison
Each scan saves a small snapshot. The next scan of the same location lists what grew, what is new and what is gone.
Clutter detection
Recognises node_modules, build output, package manager caches, virtual environments, temp folders and browser caches, and totals them.
Search and filters
Search by name across the whole scan as you type. Filter by minimum size, by age or by file type.
Duplicate files
Files of equal length are compared by content. Runs on request, not during the scan.
Size on disk
Sizes are the space actually allocated, so compressed, sparse and online-only cloud files are counted for what they occupy.
Folder levels
The treemap opens four levels of folders by default and draws deeper ones as a single block. The limit is adjustable.
Themes
Two themes, each in light and dark. English and Brazilian Portuguese.
Nothing is deleted without confirmation.
Removed items go to the Recycle Bin. There is no automatic cleanup and no one-click fix.
Scan speed
Folders are listed in bulk through the Windows directory API, in parallel on all cores. Administrator rights are not required.
| Scanned | Files | Folders | Time |
|---|---|---|---|
| A folder of source code projects | 634,060 | 67,152 | 1.9 s |
| A user profile | 2,148,709 | 574,860 | 10.0 s |
| A full system drive | 3,156,306 | 861,554 | 30 s |
Measured on the author's Windows 11 desktop with a warm file cache. A first scan after boot takes longer.
Compared with other tools
WizTree
Reads the NTFS file table directly, which is faster than walking folders, Diskplot included. Requires administrator rights. Closed source, with a paid licence for commercial use.
SpaceSniffer
A treemap with live updates. Freeware, closed source. No tree view.
WinDirStat
Open source, with a tree and a treemap coloured by file type. Diskplot adds scan comparison and clutter totals.
Questions
Is it free?
Yes. Diskplot is released under the MIT license and can be used at home and at work at no cost.
Does it need administrator rights?
No. It scans everything the current account can read. Folders it cannot open are counted and listed. Run it as administrator to include them.
Why do sizes differ from File Explorer?
Diskplot reports the space allocated on disk. Compressed files, sparse files and online-only OneDrive files occupy less than their length. A file with several hard links is counted once per name.
Does it send data anywhere?
No. The only network request is to GitHub, to check for a newer version.
Is there a version for macOS or Linux?
Not yet. Windows 10 and 11 are the supported systems.