SpaceSharp
Open-source Windows disk space analyzer with interactive treemaps
SpaceSharp is a free, open-source disk space analyzer for Windows 10 and 11, inspired by SpaceMonger.
It scans an entire drive or a selected folder and draws it as an interactive, zoomable treemap: every folder is a frame, every file a box sized by the space it uses, so the big things stand out at a glance. NTFS drives are read straight from the file table, so a million files take seconds.