SpaceSharp
Open-source Windows disk space analyzer with interactive treemaps
...Insights shows space by type, places that are safe to clear, game libraries, developer leftovers and old downloads. A duplicate finder compares file contents, and an empty folder list skips anything a program needs. Every scan is saved and compared with the last, so you see what grew. A plain-words filter, 24 palettes, dark and light themes and 18 languages round it out.
Everything goes to the Recycle Bin, except folders too deep for Explorer, which it can remove for good. Portable and installable builds for 64-bit and 32-bit Windows, code-signed. ...