Comparing FAT File Systems

The numerals in the names FAT16 and FAT32 refer to the number of bits required for a file allocation table entry.

  • FAT16 uses a 16-bit file allocation table entry (2 16 allocation units).

  • Windows 2000 reserves the first 4 bits of a FAT32 file allocation table entry, which means FAT32 has a maximum of 2 28 allocation units. However, this number is capped at 32 GB by the Windows 2000 format utilities.