Czkawka
7.4#1 in duplicate file findersFree planFree planAndroidAPILinuxmacOS
VisitCzkawka suits people who want to inspect selected folders for duplicate, empty, or other unnecessary files. It offers both graphical and command-line frontends, plus an Android frontend.
It suits Windows users cleaning duplicate files from chosen folders or drives. Pro is for coverage across 3 PCs for one year.