How do you extend partition with unallocated space in Windows 10

Diskpart is the best tool for adding more space or extending partition in Windows 10.

Hey! Extending partition in Windows 10 is generally safe if you do it right, but like with anything that involves messing with your disk, there’s always a little risk. I’ve tinkered with partition management myself, and as long as you back things up first, you should be good.

Here’s what I’d suggest based on my experience:
* Backup your important stuff. Just in case something weird happens and you lose data—that’s the one thing I always do before messing with partitions. You never know!
* Use Windows built-in tools (Disk Management). It’s pretty straightforward and safe if you’re just extending a partition into unallocated space.
* Make sure there's no ongoing disk activity. Close any programs that might be writing to your disk.
* Be cautious with third-party tools. If you go for a third-party partition manager, pick a reputable one. They’re usually safe, but always read reviews.

I did extend partition in Windows 10 and get more space, and as long as I didn’t interrupt the process, it went smoothly. Just keep your system stable (don’t shut down or restart during the process), and you’ll be fine.

When the built-in tools like Disk Management or DiskPart can’t extend a partition especially when unallocated space is not adjacent, third-party disk manager tools like Dr.Partition provide a more flexible and user-friendly way to extend partition in Windows 10 PC.

Step 1: Open the program. It will display a visual map of all your disks and partitions.

Step 2: Click on the partition you want to enlarge (e.g., the C: drive).

Step 3: From the left-hand menu or right-click context menu, choose “Resize/Move Partition”.

Step 4: If there is unallocated space next to the selected partition, drag the partition border to occupy that space.

Step 5: After adjusting the partition size, click “OK” to confirm. This will add more space to the partition.

Step 6: Click “Apply” (usually in the upper-left corner) to execute the pending operations.

Dr.Partition is a powerful and user-friendly disk management tool for Windows 11 and Windows 10. Unlike the built-in Disk Management or DiskPart, Dr.Partition allows you to extend a partition even when unallocated space is not adjacent, thanks to its smart partition-moving feature. Whether you're running out of space on your system drive or need to enlarge a data partition, Dr.Partition makes the process simple and safe.

If you prefer to use the command line to extend the NTFS-formatted D drive partition in Windows 10, here is a method I actually tried, which is relatively direct and effective. Try to extend windows partition with unallocated space as following steps:

Open the Command Prompt
I first typed "cmd" in the search box, then right-clicked "Command Prompt" and selected "Run as Administrator".

Start the Diskpart tool
Type diskpart in the command prompt and press Enter to enter the Diskpart environment.

diskpart

Select the disk
Type list disk to display all disks. I found that the D drive was on "Disk 1", so I typed:

select disk 1

Then press Enter to select the target disk.

Select the partition
Type list partition to list all partitions. Find the partition corresponding to the D drive, then type:

select partition X

Where X is the partition number of the D drive, press Enter.Type the command:

extend

If there is no unallocated space next to the D drive, I can compress other partitions to free up space. For example, select an adjacent partition:

select partition Y shrink desired=5000

Then press Enter, which will use the unallocated space to extend the D drive. If there is enough unallocated space, extend partition in Windows 10 will succeed.

Through these two command line methods, I successfully extended the partition using extend partition in Windows 10 and command line commands without third-party tools.

Although the Diskpart command line operation is efficient and does not require additional third-party tools, its operability and security are relatively low and it is suitable for users with certain experience. If you are not familiar with the command, it is recommended to use a more intuitive tool.

Using the Disk Management tool to extend a Windows partition in Windows 10 can have several disadvantages, including:

• Data Loss Risk: Although generally safe, shrinking or extending partitions always carries a small risk of data corruption or loss if errors occur during the process or if the operation is interrupted (e.g., power failure).
• Limited Shrink/Extend Options: Disk Management may not allow you to shrink or extend partitions beyond certain limits. For example, it might not be able to shrink a partition if there are immovable system files near the end of the partition, resulting in less unallocated space than desired.
• Performance Impact: Moving or resizing partitions can temporarily impact system performance during the operation, especially if the partition contains system or frequently used files.
• Potential for Errors: Using Disk Management for complex resizing might lead to errors or failures, requiring advanced tools or reinstalling partitions. Disk Management only works with basic disks; if you are using dynamic disks, this method may not be applicable or could cause complications.

To extend partition in Windows 10. While using Disk Management is convenient and built into Windows, it may not be suitable for all situations, especially when dealing with complex partitions, large data, or the need for more flexible and safer tools like third-party partition managers.

DiskPart is a powerful command-line utility built into Windows that allows you to manage disks and partitions, including extending them—provided there's unallocated space immediately after the target partition.

 How to extend partition in Windows 10 with diskpart

1. Press Win + R, type cmd, then press Ctrl + Shift + Enter.

2. Launch DiskPart:

diskpart

3. List available volumes:

list volume

This displays all volumes (partitions) on your drives. Identify the volume number you want to extend (look at the "Label" and "Size").

3. Select the target volume (Replace X with the number of the volume to extend.):

select volume X

If you want to use all available adjacent unallocated space for extending partition in Windows 10:

extend

Or, specify how much to extend in MB:

extend size=XXXX

Replace XXXX with the number of megabytes (e.g., extend size=10240 for 10GB).

Notes:

If the Extend command fails, it’s likely because the required unallocated space isn't adjacent or the partition isn't NTFS.

DiskPart won't move other partitions to make space. Use a third-party tool in such cases.

To extend the NTFS-formatted D drive partition in Windows 10, there are usually two ways to try, and here I share my actual experience.

Method 1: Extend the partition using the Windows Disk Management tool
In Windows 10, I have tried to extend the D drive partition using the built-in Disk Management tool. First, open the Disk Management tool (right-click "This PC" > "Manage" > "Disk Management"). I saw some unallocated space next to the D drive, so I just right-clicked the D drive and selected "Extend Volume".

Then, I followed the prompts to complete the wizard to extend the volume, selected the unallocated space, and after clicking "Next", the system automatically completed the partition extension. The whole process was very smooth because the unallocated space was next to the D drive at that time.

The key point is that when extending partition in Windows 10, the unallocated space must be located behind the target partition, otherwise you cannot choose to extend the partition.

Method 2: Use the Disk Management tool to shrink other partitions to create unallocated space
If there is not enough unallocated space, I have created unallocated space by shrinking other partitions. The process was simple:

 I first found a neighboring partition in Disk Management, right-clicked it and selected "Shrink Volume". I entered the desired amount to shrink, thus freeing up the unallocated space.

I was then able to extend the Windows partition with unallocated space, just like the first method, by right-clicking on the D drive and selecting "Extend Volume", selecting the unallocated space I had just freed up.