Macos – Resize NTFS partition from Mac OS X

You can be able to resize your ntfs primary partition through Ubuntu live disk or gparted live disk.

1. Boot from gparted live disk or Ubuntu live disk.If you boot from Ubuntu live disk, then click on Try Ubuntu option on startup.By default, gparted utility would be installed on Ubuntu live disk.Open gparted partition Editor from dash(An alternative to Windows Start Button on Ubuntu).

2. Let us assume, your partitions would be look like this.

   

   Linux disk naming system was completely different from Windows disk naming system.In the above screenshot /dev/sda refers to your first disk.And /dev/sda1,/dev/sda2,.., refers to the partitions present in your first disk.

3. Assume /dev/sda2 is your ntfs primary partition(Where you're going to install Windows ).IMO you are willing to add 2.73 unallocated space to your /dev/sda2 ntfs partition.I'm going to explain how to add that unallocated space to your /dev/sda2 primary partition with the above screenshot as an example.

4. To resize your ntfs primary partition, you have to get out of the unallocated space from the extended partition and move that unallocated space just below to your ntfs primary partition.The unallocated space is not present below the extended partition, it's inside the extended partition(take a look at the screenshot clearly).

5. Right-click on the /dev/sda5 and select Resize/Move option.Now, move the /dev/sda5 partition by click and move the dragger to the extreme right, so that the unallocated space will comes above to the /dev/sda5 partition.

   

   Now your partitions will looks like this,

   

6. Now, right-click on that /dev/sda3 extended partition and select Resize/Move option.Shrink it's space, so that the unallocated space present inside the extended partition will comes out of that(just above to the /dev/sda3 extended partition).

   

7. Oh, it comes out of the extended partition.Now you can be able to increase the size of your ntfs primary partition(/dev/sda2)

Note: Make sure that all the partitions are unmounted, before doing the above operations.It takes some time according to the size of your extended partition while moving between the partitions, so be patient.Finally don't forget to take backup of all your important datas.

You can use /Applications/Utilities/Disk Utility.app for that. It allows non-destructive resizing of partitions. See for example this article on how to do this. Alternatively, you can use the diskutil command line tool, see here.

Although it's possible to resize without data loss, you should always have a backup at least of your more important data on that disk. Power outages and system crashes while reformatting a disk aren't fun.

Once your HFS+ partition's size is reduced, you can create a new partition in the empty space (though you cannot create NTFS partitions from OS X).