The Australian Shepherd is a dog of medium size, showing that he is active, has strength and stamina. With a smooth, free and easy gait. He exhibits great agility of movement with a well-balanced stride. Aussies must be agile and able to change direction or alter gait instantly. Solidly built with moderate bone, the male structure reflects masculinity without coarseness, females appear feminine without being slight of bone. Males weigh approximately 50 to 65 pounds, measuring from 20" to 23", and females weigh about 40 to 55 pounds, measuring from 18" to 21". The body should be slightly longer than it is tall.

​

The head is clean cut, strong, equal in length and width and in proportion to the rest of the body. The ears should be triangular in shape, of moderate size, rounded at the tips and sit high on the head. They should be long enough for the tips to reach the inside corner of the eye. At full attention they break forward and over, or the the side as a rose ear. The muzzle is equal in length or slightly shorter than the back skull. The muzzle tapers little from base to nose and is rounded at the tip. Blacks and Blue Merles have black pigment on their nose, eye rims and lips. Reds and Red Merles have liver/brown pigment on their nose, eye and lips. Any combination of eye color is acceptable in the breed standard, so long as the eyes are healthy. They may have solid colored eyes, bi-colored, split eyes, marbled or fleaked. The eyes should be expressive, almond shaped, medium sized and well defined.

The neck is strong, of moderate length, and fits well into the shoulders. Their top-line (back) is level and strong. The chest is nor broad but deep, with the lowest point reaching the blows. Ribs are long and the underline shows a moderate tuck-up. Legs are straight and strong, have moderate bone. The pastern is medium length and very slightly sloped. The front dewclaws are usually removed while the back dewclaws must be removed; this is done between 2-3 days of age. Feet are oval, compact with close kit, well arched toes. The width of the hindquarters is equal to the width of the forequarters at the shoulders. Stifles (knees) are clearly defined, hock joints moderately bent. The hocks are short, perpendicular to the ground and parallel to each other when viewed from the rear. 

​Australian Shepherds are usually born with a long straight tail, that will either become docked or banded within 2-3 days of birth. However, you can come across a few Aussies that will be born with natural bob tails (NBT). The breed standard states that the tail not exceed 4" in length.