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3 Ways: How to Increase C Drive Space in Windows 10/8/7

Is your C drive out of space? How to increase C drive space so as to optimize the performance of your computers? This page will guide you to easily increase space in C drive in Windows 11/10/8/7. Read on to extend C drive space for free with three reliable disk partitioning tools - Disk Management, CMD, EaseUS Partition Master.

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Updated on Apr 22, 2024

This page introduces how to increase C drive space in Windows 10/8/7 so as to extend the C drive, speed up your PC, and optimize your computer's performance. It also elaborates on the advantages of why we need to increase C drive space. Now, let's see how to enlarge your system C drive on your computers. 

If you are a Windows 11 user, follow this link to see how to extend c drive in Windows 11 with success.

How To Increase C Drive Space in Windows 10/8/7 for Free?

In this part, we'd like to introduce 3 best disk management tools to you and you can pick up one of them to extend your system C drive in Windows 11/10/8/7 for free or free up disk space on Windows 8 or Windows 11/10.

Here is a comparison table that will help you to decide which tool suits your need the most in increasing C drive space:


EaseUS Partition Master

Windows Disk Management

DiskPart CMD

💻Increase C drive with adjacent unallocated space
📀Extend C drive space with non-adjacent unallocated space × ×
👩‍💻Best for For all levels of Windows users, beginners' best choice Experienced Windows users IT Administrators

Pick up one of the free methods and follow the respective tutorial as shown below to start extending your local disk C drive now. These methods also work to extend data volumes on your PC.  

If you prefer the easiest solution that helps increase C drive space in Windows 10/8/7/XP/Vista with success, EaseUS Partition Master Free, with its advanced disk partitioning features, is here to help.

Method 1. Increase C Drive Space with EaseUS Partition Master

  • Price: $0
  • Complex Level: ⭐⭐
  • Tools: computer, EaseUS Partition Master.

EaseUS Partition Master, a free partition manager software, is designed with a simple and intuitive interface for Windows users at all levels. It supports free partition management, including increasing C drive space, shrinking or extending partitions, merging non-adjacent partitions, etc.

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Video Tutorial: Increase C Drive and Manage Hard Drive Partition in Windows

Step-by-step Guide: Enlarge C Drive Space in Windows 10/8/7

If there is unallocated space on your system disk, you may go to Step 2 and start by right-clicking C drive and selecting "Resize/Move":

Step 1: Free up unallocated space for C drive.

If there is no unallocated space on the system disk, go to Partition Manager and right-click on a partition next to the C: drive and select "Resize/Move".
Drag left panel of the partition to shrink and leave unallocated space behind the system C: drive and click "OK".

Step 2: Increase C drive space.

1. Right-click on C: drive and select "Resize/Move".

Extend System partition

2. Drag the system partition end into unallocated space so to add space to C: drive and click "OK".

Add space to C drive

Step 3: Keep all changes to extend C: drive.

Click the "Execute Task" and click "Apply" to keep all changes so to extend the system C: drive.

Confirm to extend system C drive

Video Guide: How to Increase/Extend Local C Space in Windows 10

This video guide recorded by ProgrammingKnowledge2 will explain how to extend C drive in Windows 10 with Disk Management, working for all brands devices.

  • Open Disk Management - 0:32~0:44
  • Shink and create volume - 1:42 ~ 5:10
  • Enable advanced system settings - 5:11 ~ 5:47
  • Change the location of page file  - 5:48
  • Reboot to save settings - 6:43
  • Extend volume - 7:46

Did you successfully increase disk space by using this way? If you did, share this way with your friends.


Method 2. How to Increase Disk Space with Windows Disk Management

  • Price: $0
  • Complex Level: ⭐⭐⭐
  • Tools: computer, Disk Management.

Disk Management is a Windows built-in tool that supports increasing partition size with its "Extend Volume" feature. However, the program has some limitations in increasing disk space:

  • Extend Volume only works on NTFS and RAW partitions. FAT32 and other file systems are not supported.
  • The Extend Volume will grey out if no adjacent unallocated space is behind the target partition.

So, the ways to increase C drive with or without adjacent unallocated space are different. Open Disk Management, and follow the right tutorials listed below to extend the local disk C drive on your own now:

#1. Increase C Drive Space with Adjacent Unallocated Space

Step 1. Right-click This PC/My Computer, click "Manage," and select "Disk Management" under Storage.

Step 2. Locate and right-click on the local disk C drive, and choose "Extend Volume".

extend c drive with disk management

Step 3. Set and add more space to your system C drive and click "Next" to continue. 

Step 4. Click "Finish" to complete the process.

Note that if that unallocated space on your system disk is not behind the C drive, you can't extend the C drive in Disk Management. In this case, you can turn to EaseUS Partition Master with tutorials, as shown in Method 1, for help.

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#2. Extend C Drive without Unallocated Space or No Continuous Unallocated Space

To add unallocated space to C drive:

Step 1. Right-click on This PC/My Computer, and select "Manage" > "Disk Management."

Step 2. Right-click the adjacent partition next to the C drive (it would be D drive by default), and choose "Shrink Volume."

Step 3. Enter the amount of space to shrink, and click "Shrink" to confirm.

Shrink volume

Step 4. Right-click on the local disk C drive and select "Extend Volume." 

Step 5. Follow the on-screen instructions to add more space to the system C drive.

Method 3. How to Extend C Drive Space with DiskPart CMD Commands

  • Price: $0
  • Complex Level: ⭐⭐⭐⭐
  • Tools: computer, Command Prompt.

The third free method to extend system partition space is to run the CMD command using DiskPart. It's an administrator tool that might be a bit complex for normal Windows users. Therefore, you should be very careful with this process.

#1. Extend C drive with Contiguous Unallocated Space 

Step 1. Open Diskpart prompt window

  • Press Windows + R keys to open the Run dialog, type cmd and hit Enter to open Command Prompt as Administrator.
  • Type diskpart and hit Enter to open DiskPart.

Step 2. Type CMD command lines and hit Enter each time to extend C drive

  • list disk
  • select disk x (Replace X with the disk number of your system disk.)
  • list volume
  • select volume x (Replace X with the partition number of your C drive.)
  • extend size =number (Normally, the default size unit is MB.)
  • exit

After this, you can restart the PC, and you'll get a larger C drive on your computer.

#2. Extend C Drive When There Is No Unallocated Space Behind

If there is no adjacent unallocated space behind your system C drive, you'll encounter this error as shown below:

"Virtual Disk Service error: There is not enough usable space for this operation".

Can't extend c drive as there is no adjancent unallocated space next to C drive

In this case, you have two options: 1. Revert to Method 1 and extend C drive space using EaseUS Partition Master; 2. Delete the adjacent drive behind C drive to get an unallocated space.

If you prefer the 2nd option, remember to back up all user data to another location first. Now, follow the steps below to extend C drive for free:

Step 1. Open Diskpart prompt window

  • Open the Run dialog, type cmd, and hit Enter to open Command Prompt as Administrator.
  • Type diskpart and hit Enter to open DiskPart.

Step 2. Type command lines below and hit Enter each time:

  • list disk
  • select disk x (Replace X with the disk number of your system disk.)
  • list volume
  • select volume * (Replace * with the partition number that you want to delete.)
  • delete volume
  • select volume x (Replace X with the disk number of your C drive.)
  • extend size =number (Normally, the default size unit is MB.)
  • exit

After this, you can restart the PC to keep all the changes. Later, you'll see that your C drive is larger and the computer is running faster than before.

Why Need to Increase C Drive Space

Accordingly, the reasons people need to increase the C drive space vary. Mostly, it could be divided into the following two cases:

#1. C drive full, Windows warns with "Low Disk Space" message

One day, you may find the system partition (C: drive) does not have much free disk space left, and the Windows OS pops up a low disk space warning message, which states: "You are running out of disk space on Local Disk (C:)..."

low disk space warning tells you to increase c drive space

#2. Windows slows down, and computer performance goes down

As time goes by, Windows OS, installed applications, and programs will generate some application data, and cache files, which will take up huge space on your C drive. So it is to your personal user data.

With the C drive getting full, the running speed of Windows OS and the performance of your computer will go down. Problems like high CPU usage, high ram memory, Windows 11/10 update stuck, etc., come along.

If you are with one of the listed cases, the best resolution is to increase the C drive space on your computer. How to do it? You'll need a reliable disk partitioning tool that allows you to extend local disk C: drive. 

Sometimes, due to several reasons, you may want to shrink the C drive. Luckily, we've provided a detailed guide for this. Click the link below to view more information.

related articles

How to Shrink C Drive without Losing Data [2023 Full Guide]

How to shrink C drive on Windows 10? You are in the right place if you are looking for a detailed answer about shrinking C drive. On this page, you can get three free tools to successfully shrink C drive without destroying data.

shrink c drive

Bonus Tips for Increasing C Drive Space

Besides the above-presented methods, here we also have some bonus tips that can help you fix the C drive low space issue and optimize computer performance. 

Follow the tips below to get an even larger C drive and a faster computer:

1. Back-Up Big Data to An External Storage Device

If you have a certain number of big files saved on your C drive, but you don't need to use them frequently, we suggest you back up those files to an external storage device.

You may apply reliable Windows file backup software for help. 

2. Delete Useless Large Files in C Drive Regularly

Deleting the old or unnecessary files on the system drive will free up space to ensure the normal operations of the Windows system. Follow to see how to locate and delete large files in Windows 10/8/7.

3. If Extend Volume Greyed Out, Turn to EaseUS Partition Master

When you can't extend a volume using Disk Management, it's highly possible that there is no unallocated space behind your target volume. And EaseUS Partition Master can resolve this issue effectively with its Resize/Move feature. You can also apply this tool to partition the hard drive.

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Sum Up - How to Extend C Drive in Windows 11/10/8/7

On this page, we explained why do people need to increase C drive space and introduced the 3 best disk management tools for Windows 10/8/7 users to extend the system C drive and other partitions.

If you are a Windows server user, you may also refer to the listed methods as shown above to enlarge a hard drive partition. 

Increase C Drive Space FAQs

Read the following part and find the answers if you have further questions about how to increase C drive space.

1. What should I do if my C drive is full, but my D drive is still empty?

One option is to move some of your files from C to D. This can be done by right-clicking on the file and selecting "Move to." Another option is to delete some of the files you no longer need on your C drive. You can do this by right-clicking on the file and selecting "Delete." 

The final quick and easy option if your C drive has unallocated space, you can easily extend C drive space by EaseUS Partition Master. If not, you can also add space to C drive

2. How to redistribute the memory in a laptop if the C drive is full and the other drives are empty?

If your C drive is full and the other drives empty, you can redistribute the memory using a Windows tool called Disk Management. To access Disk Management, press the Windows key + R, type in diskmgmt.msc, and press Enter. In the Disk Management window, right-click on the C drive and select "Shrink Volume." This will open a new window where you can enter the amount of space you want to free up. Next, right-click on the other drives and select "Expand Volume." This will add the freed-up space to the other drives. Finally, restart your computer for the changes to take effect.

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About the Author

Updated by Oliver

Oliver is an EaseUS professional writer who dares explore new areas. With a passion for solving tech issues with straightforward guides for common users, Oliver keeps honing his writing craft by developing in-depth solutions for disk and partition management, computer boot-up issues, file transfer, etc.

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Written by Jean

Jean is recognized as one of the most professional writers in EaseUS. She has kept improving her writing skills over the past 10 years and helped millions of her readers solve their tech problems on PC, Mac, and iOS devices.

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  • I love that the changes you make with EaseUS Partition Master Free aren't immediately applied to the disks. It makes it way easier to play out what will happen after you've made all the changes. I also think the overall look and feel of EaseUS Partition Master Free makes whatever you're doing with your computer's partitions easy.

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  • Partition Master Free can Resize, Move, Merge, Migrate, and Copy disks or partitions; convert to local, change label, defragment, check and explore partition; and much more. A premium upgrade adds free tech support and the ability to resize dynamic volumes.

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  • It won't hot image your drives or align them, but since it's coupled with a partition manager, it allows you do perform many tasks at once, instead of just cloning drives. You can move partitions around, resize them, defragment, and more, along with the other tools you'd expect from a cloning tool.

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