Article ID: 195441 - View products that this article applies to.
This article was previously published under Q195441
This article describes how to determine to total amount of unused space on a drive. This is the total amount of space on a drive that is unused when clusters are occupied by files that are smaller than the clusters. For example, if a 1-kilobyte (KB) file is stored in a 4-KB cluster on a drive, there is 3 KB of unused space in this cluster.
By design, the FAT file system allocates files to the drive on a per- cluster basis. Therefore, two files cannot be stored in the same cluster at the same time. To determine the total amount of unused space on a drive, use the following steps:
TITLE : FAT Type and Cluster Size Depends on Logical Drive Size
TITLE : MS-Dos Partitioning Summary
TITLE : Description of Default Cluster Sizes for FAT32 File System