Extend partition

How to extend partition without reinstalling Windows

All new hard disks should be initialized before using, after it, you have to create and format partition. To use disk space and allocate many kinds of files more efficiently, you’d better create several volumes in a hard disk. On the contrary, there is a problem that a drive may becomes full in some day, especially for system C drive and the drives that are used to store backup files as well as other large files.

You can transfer these files and change the default file output location to other partitions, but what about the system C: drive? Start from scratch to reinstalling Windows, or replace this disk with a new larger one? NO, as long as there is free space  in any other volume of the same disk, you can transfer and add the free space to C drive. In this article, I’ll show you how to extend volume without reinstalling Operating System or losing data.

Extend partition

Which tool to extend disk drive?

To extend partition in Windows, you may either use Windows built-in tools or 3rd-party partition software.

Windows built-in tools include Disk Management and DiskPart. Disk Management is GUI component that is activated by default. DiskPart works via command prompt. The benefit of Windows Disk Management and DiskPart command is safe and fast. Meanwhile, there are many limitations that leads you to cannot extend volume.

It is much easier and without limitations to extend volume in Windows with 3rd-party partition software, however, not all software are safe. Most of computer users pay attention to the amount of functionalities and the GUI while selecting a partition software. Search by Google and you’ll find many disaster that caused by some partition software. So take care of your data, because there are family photos, videos, work projects and other important files that cannot be lost.

To ensure 100% system and data safe, NIUBI Partition Editor is the only choice. The unique innovative 1 Second Rollback technology can automatically roll back the computer or server to original status in one second, if any software related error or hardware issue such as power failure occur while repartitioning disk drives. If it happens, nothing will be changed, so the computer could back online without damage rapidly.

Note: backup software can only help you restore files, but it costs several hours to a whole day to finish. It costs much longer time to verify data and complete other works on a server.

How to extend volume in Disk Management?

To extend partition with Windows Disk Management, there are some preconditions including:

  1. The partition you want to extend should be NTFS, FAT16/32 partitions are not supported.
  2. There must be adjacent Unallocated space on the right side.

Extend Volume


  1. Press Windows and R on keyboard, type diskmgmt.msc and press Enter to open Disk Management.
  2. Right click the partition and select Extend Volume.
  3. Extend Volume Wizard will be opened, click Next to continue.
  4. Available disk and space is selected by default, click Next to continue.
  5. Click Finish to confirm and proceed the extending operation.


  • Do not delete adjacent volume D to get Unallocated space. If you do, all Windows services and program in D stop working after deleting. You’ll lose data if you forget to back up or transfer before deleting.
  • Shrink Volume can only generate Unallocated space on the right side of D, so you still cannot extend C drive except that you can move Unallocated space to behind C.

How to extend partition with Diskpart command?

There are the same limitations to extend volume with Diskpart, in addition, Diskpart has more disadvantages including:

  1. Command prompt is more difficult to use.
  2. You cannot see the disk partition layout, that means, you won’t know which drives are in a same disk.
  3. Unallocated space won’t be displayed.

So DiskPart cmd is not suggested, however, if you are interested with it, follow the steps below:

  1. Press Windows and R on keyboard, type cmd and press Enter.
  2. Type diskpart and press Enter in the command window.
  3. Type list volume to show all disk drives.
  4. Type select volume X to give focus to the volume that you want to extend, X is the number of this volume.
  5. Type extend (desired=XX), XX is the amount of Unallocated space (in MB), if you type extend without (desired=XX), all Unallocated space will be used.

Extend volume diskpart

Note: besides the limitations listed above, both Disk Management and Diskpart are executed instantly, that means incorrect operations cannot be undone.

How to extend disk partition with software?

It is much easier to extend volume with NIUBI Partition Editor, you just need to click and drag, steps:

1: Download NIUBI Partition Editor, right click D and select Resize/Move Volume.

Shrink D

In the pop-up window, drag left border rightwards to shrink it.

Shrink D

Part of free space is released from drive D and displays as Unallocated space behind C drive.

Unallocated created

2: Right click C drive and select “Resize/Move Volume” again. In the pop-up window, drag the right border rightwards to combine the Unallocated space.

Extend C drive

3: Click Apply on top left to execute, done. C drive is increased to 59.4GB by adding 20GB free space from D.

C drive extendedTips: the operations listed below Pending Operations on bottom left with can be done in Windows without reboot.

In conclusion: Disk Management and DiskPart command can help you extend volume in Windows in some part, but because of the limitations, they are not the best choices. Partition software is much easier and powerful, however, you should select a safe and reliable software such as NIUBI Partition Editor.

For Windows 10/8/7/Vista/XP (32 & 64 bit) home users, NIUBI Partition Editor free edition is 100% free and clean to resize, move, merge, convert, defrag, extend partition, etc.