Diffrent Size Avatars?

So I know the size limit on avatars is now 96X96, but I've noticed some avatars are larger then others.Some Examples:Sinharvest's avatar is 96X96, while mine is 96 x 67Ace1o1's avatar is 96 x 72 while Buppazugan's avatar is 96 x 89This isn't very important but I was just wondering what caused this and if there was a way to make my avatar the max size.Thanks in Advance!

It appears now they aren't stretched or skewed, their aspect ratio is kept when you upload them.
My avatar I created as 120x120. So when I uploaded it, it was scaled down to 96x96 since it was already a 1x1 ratio.If you want a 96x96 avatar, upload a 1x1 ratio avatar.

Ahh, I see, thanks a bunch for the help :)