How to resize drive partition on Windows 10

Windows 10 includes at least four tools to resize a drive partition, and in this guide, you'll learn how to use them all to shrink or increase the size of partition on a hard drive.

Windows 10 change partition size
Windows 10 change partition size

On Windows 10, sometimes, you may need to decrease or increase the available space of a given partition to make room to create additional partitions using the unallocated space or store more data on the same section of the drive.

Whatever the reason it might be, Windows 10 includes several tools to resize a partition without the need of formatting or risks of losing your data using the legacy Disk Management tool, Command Prompt, PowerShell, and the new Manage Disks and Volumes settings.

When you use either of these tools, you can change the partition size on the “C” drive, secondary drives, including internal and external storage and USB flash drives.

In this guide, you’ll learn the steps to shrink and extend the size of a partition on Windows 10 without third-party tools.

Change partition size using Disk Management on Windows 10

Using the legacy Disk Management tool is the easiest way to shrink or increase the partition size without formatting.

Shrink partition size with Disk Management

To reduce the partition size with Disk Management, use these steps:

  1. Open Start on Windows 10.

  2. Search for Create and format hard disk partitions and click the top result to open the Disk Management console.

  3. Right-click the drive you want to change its partition size and select the Shrink Volume option.

    Shrink volume option
    Shrink volume option
  4. Enter the amount of space you want to shrink the partition (in megabytes).

    Shrink space setting
    Shrink space setting on Windows 10
    Quick note: As you change the size value, you can confirm the total size of the unallocated space after shrinking the original partition.
  5. Click the Shrink button.

Once you complete the steps, the drive partition will be reduced to the size you specified.

Increase partition size with Disk Management

To increase the drive partition size using Disk Management, use these steps:

  1. Open Start.

  2. Search for Create and format hard disk partitions and click the top result to open the Disk Management console.

  3. Right-click the drive you want to change its partition size and select the Extend Volume option.

    Extend volume option
    Extend volume option
  4. Click the Next button.

  5. Under the “Selected” section, make sure to choose the disk with available space (if applicable).

    Quick note: In some cases, you may need to select the disk from the “Available” section, and then click the Add button to make available.
  6. Enter the amount of space you want to use to increase the drive partition (if necessary).

    Increase partition size on Windows 10
    Increase partition size on Windows 10
  7. Click the Next button.

  8. Click the Finish button.

After you complete the steps, the partition will change to the size you specified. If the “Extend volume” option is greyed out, then it means that the physical drive doesn’t have any space available that you can use to increase the volume.

Change partition size using Command Prompt on Windows 10

In the case you need to use commands to resize a partition on Windows 10 without losing data, then you can use the diskpart tool with Command Prompt.

Shrink partition size with diskpart

To shrink a partition with Command Prompt, use these steps:

  1. Open Start.

  2. Search for Command Prompt, right-click the top result, and select the Run as administrator option.

  3. Type the following command to start diskpart and press Enter:

    diskpart
  4. Type the following command to list the volumes and press Enter:

    list volume
  5. Type the following command to select the volume you want to shrink the partition and press Enter:

    select volume 4

    In the command, make sure to change 4 for the number that represents the partition you want to modify.

  6. Type the following command to determine the space you can decrease the partition and press Enter:

    shrink querymax
  7. Type the following command to shrink the drive partition by a specific amount (in megabytes) and press Enter:

    shrink desired=20480

    In the command, make sure to change 20480 for the amount (in megabytes) you want to shrink the partition.

    diskpart shrink partition
    diskpart shrink partition
  8. (Optional) Type the following command to shrink the partition by its maximum space reclaimable and press Enter:

    shrink

Once you complete the steps, diskpart will reduce the size of the partition to the new smaller size.

Increase partition size with diskpart

To increase the drive partition size with diskpart, use these steps:

  1. Open Start.

  2. Search for Command Prompt, right-click the top result, and select the Run as administrator option.

  3. Type the following command to start diskpart and press Enter:

    diskpart
  4. Type the following command to list the available disks and their capacity, and press Enter:

    list disk
    Quick note: Identify the total size of the drive with the partition you want to increase.
  5. Type the following command to list the volumes and press Enter:

    list volume
  6. Type the following command to select the volume you want to shrink the partition and press Enter:

    select volume 4

    In the command, make sure to change 4 for the number that represents the partition you want to modify.

  7. Type the following command to increase the size of the partition and press Enter:

    extend size=20480

    In the command, make sure to change 20480 for the amount (in megabyte) you want to increase the partition.

    diskpart extend partition
    diskpart extend partition
  8. (Optional) Type the following command to increase the size of the partition using all contiguous free space that is available on the drive and press Enter: extend

    extend

After you complete the steps, the partition will extend to the new size without losing your data.

Resize partition using PowerShell on Windows 10

It’s also possible to resize partitions using PowerShell commands.

Shrink partition size with PowerShell

To make a partition smaller with PowerShell, use these steps:

  1. Open Start.

  2. Search for PowerShell, right-click the top result, and select the Run as administrator option.

  3. Type the following command to list all the drives and their total size, and press Enter:

    Get-Disk
  4. Type the following command to list the available partitions on the drive and Enter:

    Get-Partition -DiskNumber 1

    In the command, make sure to change 1 for the number of the drive with the partition you want to shrink.

  5. (Optional) Type the following command to understand the minimum and maximum space you can resize the partition and press Enter:

    Get-PartitionSupportedSize -DiskNumber 1 -PartitionNumber 1

    In the command, make sure to change the number of disk and partition that corresponds to your situation. Also, the SizeMin and SizeMax are specified in bytes, which means that you may need to use an online converter to understand the information in gigabytes or any other size.

  6. Type the following command to resize the partition to 20GB and press Enter:

    Resize-Partition -DiskNumber 1 -PartitionNumber 1 -Size (20GB)
    PowerShell change partition size to smaller
    PowerShell change partition size to smaller

    In the command, make sure to replace the disk and partition number and size for the information corresponding to your drive and size you want to shrink the drive. Also, we’re using GB, but you can also specify the space in bytes, KB, MB, and TB

Once you complete the steps, PowerShell will shrink the partition to the specified size leaving additional unallocated space to create additional partitions.

Increase partition size with PowerShell

To extend the partition size with PowerShell, use these steps:

  1. Open Start.

  2. Search for PowerShell, right-click the top result, and select the Run as administrator option.

  3. Type the following command to list all the drives and their total size, and press Enter:

    Get-Disk
  4. Type the following command to list the available partitions in the drive and press Enter:

    Get-Partition -DiskNumber 1

    In the command, make sure to change 1 for the number of the drive with the partition you want to extend.

  5. (Optional) Type the following command to understand the minimum and maximum space you can resize the partition and press Enter:

    Get-PartitionSupportedSize -DiskNumber 1 -PartitionNumber 1

    In the command, make sure to change the number of disk and partition that corresponds to your situation.

  6. Type the following command to increase the partition to 40GB and press Enter:

    Resize-Partition -DiskNumber 1 -PartitionNumber 1 -Size (40GB)

    In the command, make sure to replace the disk and partition number and size for the information corresponding to your drive and size you want to increase the partition.

    PowerShell increase partition size
    PowerShell increase partition size
  7. (Optional) Type the following command to extend the partition to its maximum size and press Enter:

    Resize-Partition -DiskNumber 1 -PartitionNumber 2 -Size 64407715328

    In the command, make sure to replace the disk and partition number for the information that corresponds to your situation. Also, to specify the new size of the partition, use the SizeMax number available on step No. 4.

After you complete the steps, the partition will cover the entire available space or the specified amount.

Resize partition using Manage Disks and Volumes on Windows 10

Starting with build 20175, Windows 10 introduces a new disk management tool available through the Settings app that makes it simple to change the partition size to anything you want with only a few clicks.

At the time of this writing, the “Manage Disks and Volumes” settings are available in the latest preview of Windows 10, but because it’s still a work in progress, it may or may not work as expected.

Shrink partition size with Settings

To shrink a partition with Manage Disks and Volumes settings, use these steps:

  1. Open Settings.

  2. Click on System.

  3. Click on Storage.

  4. Under the “More storage settings” section, click the Manage Disks and Volumes option.

    Manage Disks and Volumes
    Manage Disks and Volumes
  5. Click the arrow button next to the drive to expand its partitions.

  6. Select the partition you want to shrink.

  7. Click the Properties button.

    Select partition to shrink
    Select partition to shrink
  8. Under the “Size” section, click the Change size button.

    Change size button
    Change size button
  9. Enter the amount of space you want to shrink the current partition.

    Shrink partition with Manage Disks and Volumes
    Shrink partition with Manage Disks and Volumes
  10. Click the OK button.

Once you complete the steps, the Manage Disks and Volumes settings will reflect the new change.

Increase partition size with Settings

To increase the size of a partition on Windows 10 with the Storage settings, use these steps:

  1. Open Settings.

  2. Click on System.

  3. Click on Storage.

  4. Under the “More storage settings” section, click the Manage Disks and Volumes option.

    Manage Disks and Volumes
    Manage Disks and Volumes
  5. Click the arrow button next to the drive to expand its partitions.

  6. Select the partition you want to extend.

  7. Click the Properties button.

    Partition to increase properties button
    Partition to increase properties button
  8. Under the “Size” section, click the Change size button.

    Manage Disks and Volumes change size button
    Manage Disks and Volumes change size button
  9. Enter the amount of space you want to extend the current partition. You can use any number between the Max and Min allow size. If you’re planning to use the entire space available, use the Max size number.

    Settings app increase partition size
    Settings app increase partition size
  10. Click the OK button.

After you complete the steps, the drive partition will extend by the amount of space you specified in the Settings.

Although these steps may look easier, because the feature is still under development, there’s a slightly chance that you may run into errors, which is the reason that the Disk Management tool is the preferred option to complete this task.

You can also use third-party tools like GParted to change the size or move the partition to a different section on the physical hard drive.

About the author

Mauro Huculak is a Windows expert and the Editor-in-Chief who started Pureinfotech in 2010 as an independent online publication. He is also been a Windows Central contributor for nearly a decade. Mauro has over 12 years of experience writing comprehensive guides and creating professional videos about Windows, software, and related technologies, including Android and Linux. Before becoming a technology writer, he was an IT administrator for seven years. In total, Mauro has over 20 years of combined experience in technology. Throughout his career, he achieved different professional certifications from Microsoft (MSCA), Cisco (CCNP), VMware (VCP), and CompTIA (A+ and Network+), and he has been recognized as a Microsoft MVP for many years. You can follow him on X (Twitter), YouTube, LinkedIn and About.me.