GrandPerspective

$2.99 FROM Erwin Bonsma, grandperspectiv.sourceforge. net NEEDS OS X 10.9 or later

GrandPerspective is perfect if you’re running low on legroom on your Mac and need to know which files and folders are gobbling up your free space. It scans your drives and maps them out, with larger blocks signifying larger files. Great for finding space hogs to clear them out.