To find the right height for a feeder -

 This is a rough guide and pets with joint problems may need slightly higher. Only you know your pet and how comfy they would be eating.

 Measure from the ground to top of your dogs shoulder, this is known as the wither height. Subtract 6'' for smaller dogs subtract 4''.For cats and tiny breeds probably choose a height around 7 - 12cm (unless its a very long legged cat)