What Allocation Unit Size Should I Use for an NTFS Flash Drive? For flash drives larger than 16 GB, an allocation unit size of 16 KB is recommended.

Size on disk shows the number of bytes a file has taken when you store it on a hard drive. Based on the Allocation unit size, you will see different Size on disk for the same file.

The NTFS file system has allocation unit options that usually don't matter unless there is a limitation. Rick Vanover explains how this matters for large volumes.

Windows 11/10 file systems organize your hard disk based on cluster size (also known as allocation unit size).

Is the allocation unit size in Windows' disk management tool the same thing as sector size? Sort of. On your EARS drive, a 4KB cluster contains one 4KB sector.

What Allocation Unit Size Should I Use for an NTFS Flash Drive? For flash drives larger than 16 GB, an allocation unit size of 16 KB is recommended.