Diskflag / About
About Diskflag
Diskflag is a disk space analyzer for Windows 10 and 11, made by Scott Foster at Velorank LLC. It maps a whole drive and flags what's safe to clear. It costs $8 once and runs entirely on your PC.
Why I built it
My 1 TB C drive was down to 4 GB free, and I couldn't tell why. Windows' storage page showed categories, not causes. The free treemap tools showed sizes, but not which of those folders I could actually delete.
So I wrote a scanner for my own PC. The first scan found a 112 GB Docker Desktop disk, a 65 GB page file, a 20 GB npm cache, 11.8 GB of editor snapshots, a 12.8 GB hibernation file, Chrome's 4 GB built-in AI model and four stray 1 GB temp files at the drive root. Another 102 GB was hidden from every app: System Restore points.
None of it was obvious, and most of it was safe to clear. Diskflag is that scanner, finished: one map of the drive, with the safe things marked in pink and the exact fix for each.
How Diskflag works
- It only moves things to the Recycle Bin, after you confirm. It refuses Windows folders, Program Files and your main profile folders.
- It runs offline. No account, no telemetry. Scans are saved on your PC.
- It counts size on disk, so compressed and cloud-only files don't inflate the totals.
Diskflag is honest about what it isn't. It's slower than WizTree, which reads the NTFS file table directly. It's paid where WinDirStat and SpaceSniffer are free. It's Windows only. The comparison guide says when another tool is the better pick.
The company
Diskflag is sold by Velorank LLC, a Wyoming limited liability company. Payments go through Stripe. Every purchase has a 14-day refund, no questions asked.
Contact
Email scottfoster@velorank.net. I read every message, including bug reports and feature requests.