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Checking A Drive’s Allocation Unit Size

Ryan Adams shows how to find the allocation unit size for a disk volume:

To identify the allocation unit size for a volume, we can use the fsutil.exe utility.  In the output you are looking for “Bytes Per Cluster” which is your allocation unit size. Here is an example to retrieve the information for the G:\ volume.

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fsutil fsinfo ntfsInfo G:

Ryan also shows how to change the allocation size, should you need to do so.