I copied a word document from a cruzer blade (16GB) to a cruzer edge (32GB).The first document was 1,147 KB; the copy was 1,144 KB. Should I be worried that the documents might not be identical? (The word counts and page numbers are the same.)


1) Try right-click on file name -> properties. You will see 'size' and 'size on disk'.

If 'Size' is the same for both files, the data actually saved is the same size. 'Size on disk' can vary according to the file system used, and the so-called 'allocation unit size': The data on the usb stick (on any media in general) is divided into 'blocks' or 'clusters', indicated as 'allocation unit size' when you format the media.

Any file always needs to occupy full clusters. so, if your actual data is 3.5 clusters big, the 'size on disk' will be 4 clusters. Thus, if the 'allocation unit size' on the two disks is different (for example: 32kb on one disk, and 64kb on the other), the file will use up more space on one medium than on the other.

I cite from Microsoft support, you can find more information there: Default cluster size for NTFS, FAT, and exFAT

All file systems that are used by Windows organize your hard disk based on cluster size (also known as allocation unit size). Cluster size represents the smallest amount of disk space that can be used to hold a file. When file sizes do not come out to an even multiple of the cluster size, additional space must be used to hold the file (up to the next multiple of the cluster size). On the typical hard disk partition, the average amount of space that is lost in this manner can be calculated by using the equation (cluster size)/2 * (number of files).

2) If you are still in doubt, and want to be 100% sure, open Word --> review tab --> compare. Choose the two documents. Word will individuate any differences between the two documents.

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