How to Resize Boot Partition on Windows 10 for Free

Need to resize boot partition on Windows 10

In the Windows OS, the boot partition is a partition to contain the boot loader and its supporting files. Normally, the system partition and the boot partition are in the same partition (C drive), but if multiple operating systems are installed, the boot partition will become the partition specifically installs Windows.

The boot partition is an essential partition for the operation of the computer. However, when the boot partition(C drive) is running out of space, there will be problems such as the computer running slowly or the Windows update failure. Besides, some users may wish to store personal data on a new partition instead of the boot partition.

Therefore, if there is not enough space, users may want to extend the boot partition. Besides, to create a new drive for storing personal data, they’ll wish to shrink the boot partition. In the following content, you can learn some methods to resize boot partition on Windows 10.

Resize boot partition on Windows 10 with Disk Management

Disk Management is a Windows built-in tool, it can resize the boot partition on Windows 10 with some clicks. Please refer to the following steps.

Tip: The file system of the boot partition must be NTFS and RAW, or you cannot extend or shrink it with Disk Management.

● Extend the boot partition

Step 1. Press "Windows + R", input "diskmgmt.msc" in the popped window, then hit "Enter".

Step 2. Right-click the boot partition and select "Extend Volume".

Step 3. Follow the guidance popped to complete the rest steps.

Warning: If the unallocated space is not adjacent to the boot partition, the Extend Volume will be greyed out. 

● Shrink the boot partition

Step 1. Open Disk Management as mentioned, then right-click the boot partition and select "Shrink Volume".

Step 2. Follow the on-screen instructions.

Note: If there are bad clusters or unmovable files, Shrink Volume will not work.

Resize boot partition on Windows 10 with Diskpart

Diskpart is another built-in tool on the Windows 10 to resize boot partition by typing some commands. Here are the detailed steps.

Tips:
✍ If the file system of the boot partition isn’t RAW or NTFS, you can’t resize the boot partition.
✍ Once you input and execute the wrong commands, you may lose important data accidentally.

► Extend the boot partition

If there’s adjacent unallocated space next to the boot partition, you can follow these steps:

Step 1. Click "Win+R" and type "diskpart" in the Run box, then press "Enter".

Step 2. Type "list volume" and press "Enter" to scan the existing volumes on the computer.

Step 3. Input "select volume C" and press "Enter".

Step 4. Type "extend size=30" and hit "Enter".("30" refers to the size you want to extend.)

Step 5. Input "exit" and press "Enter" to complete the whole operation.

► Shrink the boot partition

Step 1. Press "WIN+R", type "cmd" and press Enter.

Step 2. Type the following commands in sequence and hit ENTER.

✔ diskpart
✔ list volume
✔ select volume X ("X" is the volume number of the partition to shrink)
✔ shrink desired = Y ("Y" refers to the amount of space you want to shrink the partition too)

Step 3. Type "exit" and press "Enter" after the operation is completed.

Note: If there’s any bad cluster on the boot partition, you cannot shrink it.

Using free tool to resize boot partition on Windows 10

As you can see, if you resize boot partition on Windows 10 with Disk Management and Diskpart, there may be many limitations and risks. To avoid these troubles, you can try a reliable freeware- AOMEI Partition Assistant Standard.

Through this powerful tool, you can break through the restrictions of the mentioned tools. Under the humanized guidance, you can not only easily resize the boot partition on Windows 10, but also resize encrypted partition safely, even if there is no adjacent unallocated space.

You can download it to see how it works.

│ How to extend the boot partition

Here, you can see the different methods to extend the boot partition with it.

✦ Method 1: Resize partition

First, you can extend it with the "Resize Partition" feature, the detailed steps are as follows.

Step 1. Right-click the boot partition and select "Resize/Move Partition".

Step 2. Drag the little circle on the right border to the right side, then click "OK".

Step 3. Click the "Apply" to commit the operation.

Note: If the unallocated space is not adjacent to the boot partition, you can move partition first to create an adjacent unallocated space and then resize this boot partition.

✦ Method 2: Merge partition

In addition to resizing partitions, you can also extend the boot partition with the Merge Partition feature. The detailed steps are as follows:

Step 1. Right-click the boot partition and select "Advanced" > "Merge Partition".

Step 2. In the ejected window, select C drive and the unallocated space, then click "OK".

Step 3. Click "Apply" and "Proceed" to execute it.

Tip: If there is no unallocated space on the boot partition, you can turn to the Professional version to allocate free space from one hard drive to directly extend it.

│ How to shrink a boot partition

Please follow the steps below to shrink a boot partition. 

Step 1. Right-click C drive and select "Resize/Move Partition".

Step 2. Drag the little circle on the right border to the left side.

Step 3. Click "Apply" to commit the operation.

After shrinking the boot partition, you can create a partition using unallocated space for storing personal data:

Summary

Still seeking for ways to resize the boot partition on Windows 10? In this post, three methods have been shared to easily resize the boot partition without losing data, including Disk Management, Diskpart and AOMEO Partition Assistant.

In addition, if you can't do it on Windows Server 2022, 2019, 2016, 2012(R2), 2008(R2), and 2003, you can try the Server Version.