Understanding NTFS allocation unit size difference

Don’t know about you, but I have always wondered what is the difference between different allocation unit sizes, when formatting drives in Windows.



NTFS allocation unit size — Understanding NTFS allocation unit size difference

The answer is pretty straightforward. Basically, the allocation unit size is the block size on your hard drive when it formats NTFS. If you have lots of small files, then it’s a good idea to keep the allocation size small so your hard drive space won’t be wasted. If you have lots of large files, keeping it higher will increase the system performance by having less blocks to seek.

But again, nowadays hard drive capacity is getting higher and higher it makes small difference by choosing the right allocation size. The ‘’default’’ standard is formatting your drives 4096 kilobytes allocation unit size.



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