I have seen a couple of computers where the Primary partition – C Drive, has extra storage space. Some computers do not have partition at all, while some have a smaller partition. Since it is not possible to delete C drive, where Windows OS is installed, we will show you can still partition C drive in Windows 10 without formatting – using the Shrink Volume process.
What happens during the Shrink Volume process
The feature which we will use to partition C drive is called Shrink. It will make sure that files on the drive remain intact. It still creates another partition out of it. Shrink can be used from the Disk Management tool, which is available in Windows 10.
Before you start the process, make sure the C drive is not full or nearly full. If that’s the case, make sure to remove unnecessary files and have enough space.
Then, I would suggest you use the defrag tool on C Drive. It will help to speed up the shrinking process by the right margin.
When the Shrinking process starts, it arranges files such that the data are moved to one side of the physical sector. The other side stays empty, and a partition is created. That’s the reason why space is needed so it can be used temporarily.
Partition C drive in Windows 10 without formatting
As we start, there is one crucial thing you should know. The shrinking process takes time. Deleting a partition and creating a new one is a lot faster. However, that’s not an option. So make sure to have enough time to complete it.
Open the Run prompt using Win + R and type compmgmt.msc followed by the Enter key. It will open the Computer Management console.
Navigate to Storage > Disk Management, and you should see a list of all the drives and partitions inside it.
Locate the partition which says “Primary Drive.” It is usually labeled as C.
First, right-click on the C partition and select Shrink Volume.
The Disk Management tool will then query for how much space is available to shrink. It may take a while for it complete.
Next, you should see a partition creation window that displays the amount of space by which you can shrink the C drive.
Enter the desired amount and click on Shrink.
Note: You cannot shrink a volume beyond the point where any unmovable files are located. That’s the reason I had suggested to defragment the drive. If you did, you should see more space if it’s displaying less.
Post this; you might not be able to use the computer for a while. The system will be busy moving files and releasing space for the new drive.
Once the process is complete, you will see an Unallocated disk space. You will have to use this to create a new partition or volume which you can use on the computer.
Create a new partition from unallocated space
- Right-click on the unallocated disk space, and select New Simple Volume from the menu
- Enter the amount of space you would like to allocate to the free space and click ‘Next.’
- Assign a drive letter
- Type of partition, i.e. NTFS, Fat 32, etc
- After the process completes, you will have a new partition ready to use. You can choose to create multiple partitions if you wish so.
As you can see, it takes time and care to complete this. Make sure you know what you are doing and follow each step carefully. Any wrong step can result in the deletion of partition and loss of data forever.
Shrink C drive without formatting using Diskpart Command-line tool
You can achieve the same result using the Shrink command of the Diskpart tool. You can execute it on PowerShell or Command Prompt with admin permission.
Type the following and hit the Enter key-
Next type the following, and note down the number of the volume you want to shrink-
Now type the following and hit the Enter key-
select volume <volumenumber>
Lastly, type the following and hit the Enter key-
shrink [desired=<desiredsize>] [minimum=<minimumsize>]
It shrinks the selected volume to the desired size in megabytes (MB) if possible, or to minimumsize if desiredsize is too large.
If you skip specifying the minimum size, it will reclaim the maximum amount of space possible.
I hope all the steps are clear, but if you have any doubt, ask us in the comments section.