Huge inconsistency in disk space measurement, missing 50% of the disk I own a MacBook Pro 13 Retina, OSX reports disk usage as 450Gb, but utilities such as DiskInventoryX tells a different story reporting 226Gb as used disk space:



How can I convince OSX to give me back my disk space?
Given that DiskInventoryX (and other I tested) cannot find where these 411Gb marked as "Other" are what can I do to identify the issue?

Output of df -h

Device Block Size: 512 Bytes  

/dev/disk1 465Gi 421Gi 43Gi 91%  110450433 11387165 91%  
devfs      184Ki 184Ki 0Bi  100% 638       0        100%
You may be seeing the difference between used bytes versus used blocks on the disk.

If a tool iterates over the files on your disk and totals the file sizes in bytes, the total value will not match the used disk space.

Try using other disk tools to determine the remaining disk space. The df tool should provide some insight df -h.

Consider using a tool like GrandPerspective to view the contents of your drive; it appears better maintained than Disk Inventory X. Be aware that these tools show file size and not blocks used.