DiskInventor & OmniDiskSweeper shows different size as Disk Utility I am running 10.9.4 and have a 120 GB hard drive. Disk Inventory X shows only 51.9 GB of data, but About this Mac and Disk utility show less than 10 GB free space.

I tried these items:


Timemachine is off  
sudo tmutil disablelocal  
ran OmniDiskSweeper


Can you please help me understand the discrepancy in sizing?
The biggest issue here is that you need to run your analysis tools as root. If you don't do this, you'll only see the files that your account has access to, and so you won't see everything that is taking up space.

I like GrandPerspective personally. If it's in your Applications folder, the command to run it as root looks like this:

sudo /Applications/GrandPerspective.app/Contents/MacOS/GrandPerspective