Board Thread:Support Requests - Designing Your Wikia/@comment-2177054-20140326125236/@comment-4018164-20140326150634

Use these three steps: Similarly, you can use ScaleY if you want to resize the height.
 * 1) Take the width that you want.
 * 2) Check the width of the image before applying the scaleX transform (if you're using Chrome, you can do that using the Inspect Element tool, and then hovering above the image in the HTML source code. a tooltip would read the current height and width of the image).
 * 3) Devide the width that you want by the current width. The result is the value of the scaleX.