Similar to the "Details" view in Windows, WhatSize offers a file size column in a Finder-like interface. You can filter WhatSize file size and/or file type to narrow down your hunt for large files. Similar to previously-mentioned Lifehacker favorite, Disk Inventory X, WhatSize offers a granular method of displaying specific folder and file sizes.
While the app is measuring a folder the user can browse the files within that folder and immediately see the size in bytes. Hidden files, cache files, directories will all show up with their corresponding size.
WhatSize is a free download for Mac only.WhatSize [ID-Design, Inc. via MacApper]
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