JSI Tip 2120. What are the default NTFS cluster sizes in Windows 2000?

Jerold Schulman

March 7, 2000

1 Min Read
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Unlike Windows NT, when you specify that install should format a partition as NTFS, it does so directly, without the need to CONVERT the partition. Windows NT converted the partition using a cluster size (Allocation Unit) of 512 bytes.

When Windows 2000 formats a NTFS partition, the following cluster sizes default:

   Drive Size                 Cluster Size       Number of Sectors   ---------------------      ----------------   -----------------   512MB  or less             512 bytes          1   513MB  to 1024MB(1GB)      1024 bytes (1KB)   2   1025MB to 2048MB(2GB)      2048 bytes (2KB)   4   2049MB and larger          4096 bytes (4KB)   8 

NOTE You can alter the cluster size used to format a drive in Disk Management and with the /a: option of the FORMAT command.

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