Q: Why does my 1TB drive only seem to have 930GB free space? Even after an NTFS format
A: The drive manufacturers use a standard metric system to determine the drive size.
According to the packaging(marketing hype)
1TB = 1000,000,000,000 bytes
This might seem correct, but the real way bytes should be calculated is like this
1TB = 1000bytes x 1024 (kb) x 1024 (mb) x 1024 (gb)
This accounts for the 7% space exageration by the drive manufacturers. So next time you’re out buying storage, expect to loose 7% of the capacity advertised on the box.