Resize NTFS partition from Mac OS X?

Question

I have an external hard drive that I used for backups of my Windows machine. I left that machine behind but took the drive when I moved to a new city. So far, I've only bought and used a Macbook in the new city. I want to use this external drive for Time Machine, but when I first got the drive, I decided to format it in a single, large, 2TB NTFS partition. Is there a tool that runs in OS X that will let me resize an NTFS partition without losing the data?

Solution

GParted would be able to do that.
You could boot from a GParted LiveCD or a GParted LiveUSB.

Comments

[BenjiWiebe]

Do you have an objection to using the GParted LiveCD?

[John Freeman]

I would not, if this computer had an optical drive. I'm on a 2013 Macbook Pro Retina running OS X 10.9.3. Ideally, I'd like to avoid buying a drive just for this purpose, but I can ask at work to see if I can borrow one.

[BenjiWiebe]

Uhhh...Perhaps this would work then? It is the way I use it.

[John Freeman]

Oh cool, didn't see that. Maybe I can use Mac Linux USB to create it. I'll give it a shot when I get more time. Thanks!

[mb21]

Seems there are a few possibilities. iPartition worked great for me.

[John Freeman]

Tried today. Failed while booting with the error "no suitable video mode found, trying blind boot" or similar. I assume it's because it doesn't have a suitable driver for a Macbook Retina display. Is it not possible to run gparted directly from my Mac?