Maximum Sizes

The maximum file size and volume size for the FAT file system is 232 bytes (4 GB). FAT can support a maximum of 65,535 clusters per volume.

The NTFS architecture is designed to use numbers up to 264 bytes (16 exabytes, or 18,446,744,073,709,551,616 bytes). In theory, it is possible to have a volume 264 bytes in size. Even if there were hardware available to supply a logical volume of that capacity, there are other limitations to the maximum size of a volume.

Partition Tables are limited by industry standards to 232 sectors. (For more information about Partition Tables, see the sections titled "Partition Table" and "Using Hard Disks With More Than 1024 Cylinders (x86-based Computers)" in Chapter 17, "Disk and File System Basics."

The sector size is a function of hardware and industry standards, and is normally 512 bytes. While sector sizes might increase in the future, the current size puts a limit on a single volume of 2 terabytes (232 * 512 bytes, or 241 bytes).

Windows NT provides the capability to combine discontiguous disk areas when creating volume sets, and stripe sets, but these volumes have the same limitations. Even if there were physical disks with 2 terabyte (TB) capacity, they could not be combined to create larger volumes without increasing the physical sector size.

There is one case where you can combine disks that exceed the 2 TB limit. In Disk Administrator, there is an option to extend a volume set. You do this by selecting an existing primary partition, logical drive, or volume set that is already formatted as NTFS. You can then combine it with one or more areas of free space and select Extend Volume Set from the Partition menu. You end up with a larger NTFS volume set. However, if anything goes wrong with a volume set larger than 2 TB, you cannot just reformat it. You must again start with a smaller volume set (<=2 TB) and use the Extend Volume Set selection to extend the volume set to larger that 2 TB.

For the time being, 2 TB should be considered the practical limit for both physical and logical volumes using NTFS.

With the NTFS file system, you can have a maximum of 232 clusters per file. This is an implementation limitation, not a file size restriction.

There is no specific limit to the number of files on an NTFS volume. However, you will not be able to create any new files when your volume is so full that Windows NT cannot allocate another entry in the MFT.