Increase C drive space

Increase partition size on Windows 7

The same with previous Windows XP and Vista, disk partitions in Windows 7 also run out of space, especially to system C drive and the partitions for backup, multimedia and projects. Better than Windows XP, Windows 7 native Disk Management can decrease and increase partition size without third party software. However, because of some inherent limitations, you still need professional partition software in many situations.

In this article, I’ll show you how to increase partition size in Windows 7 (32 & 64 bit) without losing data.You can increase size of a drive by shrinking or merging other drives.

Increase C drive space

Extend volume with Disk Management

To increase partition size on Windows 7, Disk Management has built-in Extend Volume functionality, however, not all disk drives can be extended. As I said above, there are some inherent limitations including:

  1. Only NTFS partition is supported, FAT32 volumes cannot be extended.
  2. When you decrease drive D with Shrink Volume, Unallocated space is generated on the right side of D, but to increase C drive with Extend Volume, Unallocated space must be behind C.
  3. Unallocated space that is deleted from a Logical partition cannot be added into a Primary partition. Take the screenshot below as example, you cannot increase drive D with Extend Volume, even if you delete drive E.

Extend volume Windows 7

If there is a disk volume that fits for the requirements, you can increase volume size in Disk Management easily:

  1. Right click this drive and select Extend Volume.
  2. Simply click Next and complete the Extend Volume Wizard.

To decrease and increase drive size on Windows 7, third party partitioning software is much more powerful, but you should select a reliable tool, otherwise, there is potential system damage and data loss risk.

Increase partition size by shrinking

When a disk drive is getting full, you can shrink other drive in the same disk to get free Unallocated space and then add the space to this drive. Operating System, programs and anything else keeps the same. System C: drive is most likely running out of space and there is another drive D in the same disk, so here I’ll show you how to decrease D and increase C drive.

Download NIUBI Partition Editor, you’ll see all disk partitions on the right and available operations on the left. In my Windows 7 laptop, drive D is 50GB and C drive is 30GB.

NIUBI Partition Editor

Step 1: Right click D and select Resize/Move Volume, drag left border rightwards to shrink D in the pop-up window.

Decrease D

20GB free space is taken out from drive D and display as Unallocated behind C drive.

Unallocated produced

Step 2: Right click drive C and select Resize/Move Volume, drag the right border rightwards to combine the Unallocated space in the pop-up window:

Extend C drive

C drive size is increased to 50GB.

C drive increased

Increase volume size by merging

If there are many volumes in this disk, you may consider increase partition size by merging another drive together. NIUBI Partition Editor can move all files automatically when merging volumes.

For example, right click either drive E or F and select Merge Volume.

Merge volume

In the pop-up window, click the check-box in front of both E and F, and then click the drop-down box on the bottom to select the destination drive.

Select drives

Click OK and back to the main window, drive F is merged into E. All files in drive F will be moved to a new folder in drive E automatically.

Drives merged


  • To avoid mistake, the operations you do won’t be executed immediately, they’ll be listed as pending on bottom left, so you can preview, click Undo on top left to cancel, or click Apply to confirm and execute.
  • The operations with  can be done in Windows desktop without interruption.

In Summary

To increase partition size on Windows 7, the built-in Disk Management can only help you in restricted condition, so you still need 3rd-party software in most situations. As the safest Windows partition software, NIUBI Partition Editor is integrated with innovative 1 Second Rollback technology to ensure system and data intact. You can increase the size of a partition by shrinking or merging other volumes, and you just need to click, drag and drop on the disk map of NIUBI.

Download to try