Fixed: Changing Block Size from 4K to 64K | Complete Guide for 2024

By

Sherly 

Written by

Cici 

Last updated on April 22, 2024

Block size refers to the small units of storage that a hard drive is divided into. Most computers have a block size of 4K, but you can change this anywhere from 512 bytes to 64KB. In most cases, the default settings will be fine; however, there are certain situations where changing the block size will be necessary.

If you're looking for solutions, then you've come to the right place. Four efficient solutions are provided. Keep reading to know when and how to change block size from 4k to 64k!

How to Change Block Size from 4K to 64K - 4 Effective Methods [1] 1. Using Disk Management Tool In the Windows operating system, you can use the built-in "Disk Management" tool to adjust partition sector size. Follow these steps: a. Right-click the "Start" button and select "Disk Management." b. Locate the partition you want to change, right-click it, and choose "Properties." c. In the pop-up window, select the "Tools" tab, then click "Check" to ensure there are no disk errors. d. If no errors are found, close the window. Then, use a third-party partition tool (like tools Partition Master or MiniTool Partition Wizard) to adjust the block size, as the built-in Windows tool doesn't support direct changes. 2. Using Command Prompt If you're comfortable with command-line operations, you can use the `fsutil` command to change the NTFS file system's block size in Windows: a. Open Command Prompt (run as administrator). b. Enter the following command, replacing `X:` with your drive letter and `64K` with your desired block size: ``` fsutil fsinfo setsectorsize X: 64K ``` c. Backup your data before doing this, as it may result in data loss. 3. Third-Party Partition Software Utilize professional partition management software like AOMEI Backupper, Acronis True Image, which usually provide an intuitive interface for changing the block size: a. Install and launch the chosen partition software. b. Select the partition you want to modify and find the option to adjust the block size. c. Follow the software's instructions to complete the operation, making sure to back up important data beforehand. 4. Formatting the Hard Drive Although not ideal, if you don't mind losing data, you can format the hard drive to a new block size: a. In "Disk Management," right-click the target partition and select "Format." b. In the formatting window, you can set the "Allocation Unit Size," which is the block size. Enter "64000" (for 64K). c. Click "OK" and confirm that you're willing to lose all data on the partition. Remember to back up your data before making any changes, as these operations can lead to data loss.

There are four methods to change the hard drive block size from 4K to 64K. We'll discuss these options below, but before we do, refer to the table below to see what's available and which one might be better for you.

Obviously, using a third-party tool like Partition Master is a better choice, which can change cluster size without formatting. This will increase the success rate of resizing and simplify the operation. Of course, you can choose other programs based on your preference. We will provide detailed steps for each method.

For more information about allocation unit size, such as the best SSD cluster size, refer to the following articles:

What is the Best SSD Allocation Unit Size in Windows 11/10

On this page, we will introduce what the best SSD allocation unit size is in Windows 11/10. Meanwhile, you can also get the best solution to change it.

Option 1: Change block size from 4K to 64K using Partition Master tool

AOMEI Partition Assistant is an all-in-one disk management tool whose "Change Cluster Size" feature makes adjusting the cluster size of your hard drive easy and efficient. Additionally, it lets you create, delete, and merge partitions with ease.

In fact, with just a few clicks, you can resize the block size of a disk from 4KB to 64KB in seconds, with no loss of data.

Step 1: Right click on the partition whose cluster size you wish to modify, select “Advanced” and then click on “Change Cluster Size”.

Step 2: Click the size list under New Size, select the desired cluster size for the disk partition you want to resize, and then click OK.

Step 3: Click “Run 1 Task,” and then click “Apply” to confirm.

Other features of MiniTool Partition Wizard:

Option 2: Use Disk Management to change the cluster size from 4K to 64K

"Disk Management" is a disk tool that comes with Windows, which you can use to change the file system, create partitions, format drives, and more. You can also adjust the cluster size using this tool.

Here's how it would work:

Step 1: Type “Disk Management” into the Start menu.

Step 2. Select the disk for which you want to change the cluster size, and right-click it.

Step 3: Choose “Format.”

Step 4: Select “64K” from the “Allocation unit size” drop-down menu.

Step 5: Format the drive now.

Disk Management is a tool provided by Windows to manage disk partitions and formatting. You can also use it to perform the following tasks:

Option 3: Use File Explorer to change the cluster size from 4K to 64K

File Explorer is one of the primary ways to access different local disks and storage media on your computer. You can also use File Explorer to change the cluster size of a hard drive.

Here's how:

Step 1: Open This PC.

Step 2: Select the disk whose cluster size you want to change.

Step 3: Right-click the drive and select “Format.”

Step 4: Select “64K” from the Allocation Unit Size dropdown.

Step 5: Click the “Start” button to format the disk and change the cluster size.

Option 4: Change the cluster size from 4K to 64K via CMD

Command Prompt is Windows' command-line interpreter, which can execute various commands and troubleshooting tasks.

Here's how to change the cluster size using the command prompt:

Step 1: Click “Start” and type “Command Prompt.”

Step 2: Choose “Run as administrator.”

Step 3. Press Enter to enter the following command, which will resize the cluster.

• diskpart
• list disk
• select disk x (replace "x" with the number of the disk you want to change the cluster size for)
• list partition
• select partition m (replace "m" with the number of the partition you want to change the cluster size for)
• format fs=ntfs quick unit=64k

What are block size and cluster size?

Block size and cluster size sound like the same thing, but they're not.

A block is the unit of data that can be written to or read from a storage device. On the other hand, a cluster defines the amount of space allocated for a file, which typically spans across multiple blocks.

The main difference between block size and cluster size is that the former is a logical attribute of the file system, whereas the latter is a physical property of the storage device.

Smaller cluster sizes can improve performance with small files but waste disk space. Larger cluster sizes can slow down small files but be more efficient with larger files. However, 4096 bytes (or 4K) is typically the standard cluster size.

This strikes a good balance between performance and efficiency for most workloads. If you want to experiment with changing the cluster size or block size, this guide has more on finding the most efficient solution. And if you found this useful, please do share the link with others.

Why change the block size from 4K to 64K?

64K block refers to a storage unit of 64 kilobytes. It is a multiple of the standard block size of 4K and is typically used in file systems when dealing with larger files.

Larger clusters allow each one to store more data, reducing the time the hard drive's head needs to move from one cluster to another. And choosing a block size of 64K prevents HDD fragmentation.

Here are a few reasons why you might consider changing your disk block size from 4K to 64K:

• Improved performance for large files: If your storage device contains many large files, changing the cluster size to 64K can enhance performance.
• Saving disk space: If your storage device holds many small files, altering the cluster size to 64K can help save disk space.
• Enhanced compatibility with certain applications: Some applications require a specific cluster size. For instance, certain databases might demand a cluster size of 64K. If you're using an application with a specific cluster size requirement, you should adjust your disk's cluster size accordingly.

Conclusions

Now you know why you should consider changing the disk sector size from 4K to 64K. We also showed you how to change the sector size, but our preferred method is to use the Partition Master tool because it's easy to use, and you can change the sector size in a matter of seconds.

In addition, Partition Master offers several other disk-related tools, and it's very easy to use, making this a no-brainer.

Frequently Asked Questions (FAQ) About Changing Block Size from 4K to 64K

Got more questions about changing block size from 4K to 64K? We've got you covered right here.

1. Does block size really matter?

Yes, block size is important. For smaller files, an HDD can read them faster with a smaller block size, but for larger files, a block size of 64K is better, as it puts less stress on the drive when searching for files.

2. What is the size of a Windows 4K block?

A 4K block is actually 4,096 bytes in size.

How do I check the sector size of a disk in Windows?

Here's how to check the block size:

1. In the Start menu, type "System Information." 2. Expand "Components," then select "Storage." 3. In the right-hand window, locate "Bytes per Sector." 4. The number displayed next to "Bytes per Sector" is your hard drive's block size.

How can I change the cluster size without formatting?

The best way is to use a partition master tool to change the cluster size without formatting. In this way, you can easily change the cluster size without losing any data.

Here's how to change the cluster size without formatting:

1. Right-click on the partition you want to change, and select "Advanced." 2. Expand the "New Size" dropdown menu and choose "64K." 3. Click "OK," then "Apply" in the pop-up window.