By Lucas / Last Updated March 4, 2022

Why do you need to shrink C drive?

Shrinking volume from C drive takes fully advantages of a hard disk that does not using its all space. For example, you have a 200GB hard drive with only C drive partitioned and there are 50GB in size has been used. You may want to shrink C drive to 100GB for system files and make a new partition for personal data or new released system with the generated space.

Some users want to shrink C drive and extend D drive with the redundant space. This may result from unreasonable partition layout when they first partition the hard drive, which may make hard drive management harder.

Anyway, no matter what factor leads you to shrink the system drive, the most important thing is to find out how to do this. Following parts will discuss three methods about shrinking C drive in Windows.

Shrink C Drive with Windows Built-in Tools

Here in this tutorial, it will take shrink C drive partition Windows 7 for example. However, before you start, clean up some of the crap first. For instance, empty the recycle bin and delete useless files on the C drive. Next, create a system image for your computer. These methods won’t cause data loss but you cannot be more careful in dealing with system and data.

Disk Management: Shrink C Drive in GUI

Firstly, right-click "Computer"-> "Manage"-> double click "Disk Management" and right-click the C drive, select "Shrink Partition". It will query volume for available shrink space.

Shrink Volume Disk Management

Secondly, type in the amount of space that you want to shrink by or click the up and down arrows behind the box (no more than 37152 MB).

Shrink c drive Disk Management

Finally, you will see the unallocated space next to C drive.

Result Disk Management

Shrink C Drive Command Line

Diskpart is one of the built-in partition tools in Windows, which is an embedded product that needs to be used under Command Prompt. Press + key at the same time to start Run box.

• Type cmd and press Enter key to start Command Prompt.

• Input Diskpart.exe and press Enter to start Diskpart to shrink C drive.

• Input list volume and press Enter.

• Input select volume x (x is the volume number you want to shrink) and press Enter.

• Input shrink desired=10240 (size stands for the capacity you will shrink by and the unit is MB) and press Enter.

• Input exit and press Enter.

Cannot Shrink C Drive?

When shrink C partition with Disk Management, you are likely to encounter one confusing situation. For example, you have 909 GB on your C drive. However, when you plan to shrink this partition only to find the available space is only 297 MB according to the querying results. While at the top of the screen, it indicates that C drive has 472 GB of free space. What is wrong?

Well, the answer is the size of the available shrink space can be restricted by the amount of space currently allocated to on the hard drive for the virtual memory page file, system protection maximum storage space size, and hibernation files. The location of the files on the hard drive plays a big part here because these files are marked as unmovable. Disk Management is unable to relocate them. If these files are located in the middle of the total amount of free space on the disk, then only the free space on the other side (usually its right side) can be used to create a new partition. And the same situation like before appears. What’s worse, even though there are no obstructive unmovable files, you can only shrink half space of the total amount with Disk Management.

Best Free Software to Shrink C Drive

It is time to turn to third-party partition manager when Windows snap-in programs won’t work. You can try AOMEI Partition Assistant Standard (free) which can relocate those files without damaging any of them. It is an all-around and comprehensive application that integrates simple-to-handle options for disk and partition management. The Standard edition is a freeware that has earned good reputation among worldwide users. It can also be used to shrink C drive in VM machine.

To shrink C drive in Windows Server like Server 2003, Server 2008, Server 2012, Server 2016, etc, you can refer to AOMEI Partition Assistant Server edition.

How to Shrink C Drive beyond Limit via AOMEI Partition Assistant?

Step1. Download, install and run this software. Right-click C drive and select "Resize Partition" or select this option in the left panel (you can see the free space of C drive is 29.87 GB).

Resize System Partition

Step2. Type in the amount of space or drag the double-headed arrow to resize.

Shrink System Partition

Step3. A gray unallocated space just behind C drive, click "Apply" to execute operations.

Apply Resize System Partition


  • In the window "Pending Operations", you need to confirm these operations and click "Proceed".
  • The C drive is in using, so the program will finish these operations in restart mode automatically.

Proceed Resize System Partition

Tips: To shrink C drive and extend D drive, you can select "Merge Partitions" to add the generated unallocated space to D drive. This method also applies to shrink D drive and expand C.

To sum up, AOMEI Partition Assistant can help you do the task that the built-in tool can’t. Another way to make use of space in C drive is to create partition in C drive directly. For more information, see how to partition C drive. Except for shrinking C drive more than half space, you can use it to move partition, merge partitions, copy disk, convert system disk from MBR to GPT disk for Windows 11, and more advanced function, command line partition.