SpaceScan

Finds what is filling up a Windows drive. Free, no limits, no nagging: it reads the NTFS Master File Table directly, so a whole drive — including a 10 TB one — is mapped in seconds.

What it does

• Folder tree with a size bar, percentage of the parent folder and the file count on every row.
• Whole drives in seconds. On an NTFS volume it reads the MFT (like the fast commercial tools). Anywhere else — a folder, a network share, a non-NTFS disk — it walks folders instead, with no path-length limit and without following junctions.
• File types and categories: where the space goes per extension, or grouped into Video, Photos, Archives, Installers and the rest.
• Largest files on the drive, and a search by name, minimum size and age that also runs off the MFT.
• Duplicates: same size, then the same hash of the first 64 KB, then of the whole file, with the space you would get back.
• Compare a scan with an earlier one and see what grew. Every scan is stored automatically.
• Delete, copy or move straight from the results, several items at once, through the Windows dialogs you already know.
• Export to HTML or CSV, and a command line for scheduled reports.
• Exclusions by name, extension or path, kept between runs.
• Works with Shelf and Backup Labs when they are installed: a game's folder is labelled with the game, and a game Shelf can move has "Move this game to another drive (Shelf)" in its row menu, which opens Shelf's own move; Backup Labs' folders are labelled too, and a folder can be backed up from there.

Command line

Runs without a window, for Task Scheduler and scripts:

SpaceScan.exe D:\ --report D:\report.html --compare-last
SpaceScan.exe C:\Users --csv users.csv --exclude "node_modules;*.iso"
SpaceScan.exe --help

Reading the MFT needs administrator rights; in Task Scheduler tick "Run with highest privileges". Given just a path, SpaceScan opens its window and scans there — that is what the Explorer and File Labs right-click entries use.

Requirements

Windows 7 or later, including Windows Server. Nothing to install alongside it: the app is built against the .NET Framework that ships with Windows.

Building

build.cmd            compiles SpaceScan.exe
.\build.ps1          compiles, draws the icon and builds the installer (needs Inno Setup 6)
.\check.ps1          self-checks; run it elevated to cover the MFT paths too

Licence

MIT — see LICENSE.

More from Protagonist Labs

• Shelf: every PC game in one library, with the size of each install.
• File Labs: a free dual-pane file manager.
• All apps: Windows apps that each do one job properly.