How to Use Unallocated Space in Disk Management | Windows Tutorial 2024

This page gives you an overview of unallocated space on storage devices as shown in Disk Management on your Windows computer. Let's explore what unallocated space is, what you can do with it, and how to use it in Disk Management.

What is Unallocated Space | Definition of Unallocated Space?

Unallocated space, also referred to as “free space” by some Windows users, refers to unused areas or a certain amount of storage space on a hard drive, SSD, external hard drive, USB flash drive, or SD card.

More specifically, unallocated space refers to a portion of storage space that hasn't been assigned to any partition. For instance, Windows defines physical space on a storage device that isn't part of any partition as unallocated. You can easily view the unallocated space on a disk in Disk Management by following these steps:

Step 1. Right-click the Windows icon and select Disk Management to open Disk Management.

Step 2: After opening Disk Management, you can view the unallocated space on your hard drive.

Unallocated space exists on all types of storage devices, such as hard drive, SSD, external hard drive/SSD, USB flash drive, SD card, and so on. So what can I do with unallocated space? And how to use the free unallocated space on a drive? All the questions will be answered in the following parts.

In disk management, what can unallocated space be used for? [Advantages and Benefits]

Having unallocated space on a storage device opens up a number of possibilities for Windows computers and external storage devices.

Here are some reasons why we often recommend that you keep some unallocated space on your hard drive, especially on the system disk:

• Unallocated space enables users to create new simple volumes in disk management and store files on hard drives, SSDs, and external drives.
• When encountering the low disk space error, unallocated space allows you to flexibly extend partitions.
• Unallocated space helps to expand the C drive, instantly resolving the issue of slow computer performance.

In addition to the above, you can use an unallocated drive to install Windows or even macOS on your computer. In any case, Windows or macOS must be installed on a completely unallocated drive. To do this, you need to delete all partitions on the drive and make the entire disk unallocated.

So, how to use unallocated drive or unallocated space on your storage device? Read on the next section, where we'll walk you through a complete guide on how to use unallocated free space in Windows Disk Management.

How to Use Unallocated Free Space in Disk Management

In Disk Management, you can perform two main operations on unallocated space on a disk:

1. 1. Create a new simple volume or partition a new hard drive/SSD.
2. 2. Extend an adjacent or non-adjacent partition.

Refer to the appropriate guide for instructions on how to use the unallocated space on your hard drive now:

#1. Create a New Simple Volume or Disk Partition

Step 1: Right-click the Windows icon and select “Disk Management” from the list.

Click "Disk Management".

Step 2. Right-click on the unallocated space and select "New Simple Volume..."

Step 3: Adjust the size, file system format, and drive letter of the new simple volume, then click Next.

Step 4. When you're done, click Finish.

If the disk is new and no space has been allocated on it, you can repeat this process to create as many partitions as you like.

#2. Extend Adjacent/Neighboring Partition or Add Unallocated Space to C Drive

When unallocated space is adjacent to the partition you want to extend, you can directly expand the volume using the unallocated free space.

Note that the unallocated space must be adjacent to the volume you want to extend, either in front of or behind it on the drive.

Here, we'll use this example to show you the entire process of adding unallocated space to Drive C:

Step 1: Open Disk Management by right-clicking the Start button and selecting Disk Management from the list.

2. Right-click on Drive C or the target volume, and then select “Extend Volume.”

Step 3: Select the “Unallocated” space, then click “Next” to proceed.

Step 4: Click on “Finish”.

#3. Allocate unallocated space to a non-contiguous partition for extending it

If you have unallocated space on your hard drive but it's not adjacent to the target volume, you need to find a way to move this unallocated space. Disk Management cannot do this for you; you'll need professional help from a partition manager software.

"Partition Master" can meet your needs. You'll need to install it on your computer and use it to move the unallocated space.

Here is how it could work:

< strong > 1. Move unallocated space next to the target partition

Step 1: Select the partition next to the unallocated space and choose “Resize/Move”.

Step 2: Place the mouse pointer on the partition and drag it left or right to move the unallocated space.

You can repeat Steps 1 and 2 to move unallocated space to where you want it.

Move unallocated space to where you need

Step 3: Click "Apply" and then "Proceed" to perform the operation, which will add the unallocated space to the target partition.

2. Extend a partition using unallocated space

Step 1: Open Disk Management, and right-click the target volume.

Step 2: Select "Extend Volume" and click "Next" to proceed.

Step 3. When the extended partition process is finished, click on “Finish”.

After going through these steps, you have successfully used the partition manager software and the disk management tool to extend non-contiguous partitions into unallocated space.

Unallocated Space Troubleshooting: Fix Unallocated Space Issues on Windows

During the use of hard disk and storage devices in Disk Management, you may encounter some issues related to unallocated space.

Here, we'll outline the three most common issues and provide comprehensive guides to help you address them effectively. Let's get started.

1. Unable to Extend C Drive on Windows 10 with Unallocated Space

There could be many reasons why you can't extend C drive with Disk Management, you can open it and check if your disk is listed in the following situations.

If possible, successfully extend the C drive following the appropriate steps:

1.1 Unallocated Space not next to System C Drive

If the unallocated space is not next to Drive C, you can use the Partition Master tool to move the unallocated space behind Drive C as described above, and then proceed with Method 3<a class="anchor" href="#3">3</a>.

Then extend the C drive by adding the unallocated space to it through Disk Management, as shown in method 2.

< strong > 1.2 There is no unallocated space left on the operating system disk

There are two methods you can take when there is no unallocated space on Windows disk:

#1. Shrink the邻近 volume and expand C drive

When there's enough free space on the partition next to C:, you can shrink it and add the unallocated space to C: following these steps:

• Open Disk Management, right-click on the partition following drive C, and select "Shrink Volume..." • Specify the amount of unallocated space you want to reserve from drive C, then click "Shrink."

1. Right-click on the C drive and select "Extend Volume...", then click "Next" to proceed. 2. Finally, click "Finish" to complete the process.

#2. Allocate Space from Another Disk to C Drive

When the space beside System C drive is insufficient, you can use a partition assistant tool to allocate free space from other existing partitions to C drive.

Please refer to this guide for instructions on how to proceed:

Step 1: Right-click on Drive D, which has enough space, and select "Allocate Space."

Step 2. Select the target partition - C: Drive, and then drag the partition panel to the right to add the available space of D: Drive to C: Drive. Then click “OK” to confirm.

< strong >Step 3. Click on "Execute Task" and then "Apply" to start the process of moving space from Drive D to Drive C.

What if there is not enough unallocated space on the target disk?

If there is not enough unallocated or free space on your data disk to save more data, you can convert the current disk and the second disk to a dynamic disk, and then merge the two disk spaces into one.

This way, you can extend the current disk's space into the second disk. Here's how:

Step 1: Open Disk Management, right-click the source disk and select "Convert to Dynamic Disk"…

Step 2: Check the hard drive(s) you would like to convert to dynamic disk.

Here, you can select the source disk and target disk, then click “OK”.

Step 3: Click “Convert” to start converting both disks to dynamic disks. Then click “Yes” to confirm.

4. Right-click the partition you want to extend, and select “Extend Volume.”

Select “Extend Volume”

Step 5: Then select the target disk and click "Add" and then "Next".

Step 6. Finally, click “Finish.”

This way, you can use unpartitioned space on either drive – or on as many drives as you like.

3. What should I do if Disk 0 and Disk 1 are unknown, uninitialized, and unallocated?

When your disk shows up as unknown, uninitialized, and unallocated, it's likely that you have a brand new disk that hasn't been initialized yet.

To make the most out of your hard drive and rescue it from being unknown, uninitialized, or unallocated, you can initialize the hard drive via Disk Management and then create partitions with the unallocated space.

Here is how it could work:

First, open Disk Management, right-click on the disk, and select "Initialize Disk".

Second, set the disk partition style for the drive: MBR for disks under 2 TB, and GPT for those 2 TB and over.

Third, right-click on the “Unallocated” space and create a new simple volume on your disk through Disk Management, as shown in Method #1.

Conclusions

Unallocated space refers to the unused and free physical storage space on a hard drive, SSD, USB, or SD card. It presents high possibilities for creating volumes, extending partitions, or even setting up a new disk for a Windows installation or a disk upgrade.

Therefore, when you come across unallocated space on your disk, don't panic. You can make use of the unallocated space by employing the solutions provided on the page in Disk Management.