The AKC Labrador Standard

"The Labrador Retriever coat colors are black, yellow and chocolate. Any other color or combination of colors is a disqualification. A small white spot on the chest is permissible, but not desirable. White hairs from aging or scarring are not to be misinterpreted as brindling. Black— Blacks are all black. A black with brindle markings or a black with tan markings is a disqualification. Yellow—Yellows may range in color from fox-red to light cream with variations in shading on the ears, back, and underparts of the dog. Chocolate—Chocolates can vary in shade from light to dark chocolate. Chocolate with brindle or tan markings is a disqualification." 

The Labrador Retriever is a strong looking, short-coupled dog with a dense, short, hard coat, a broad skull, a powerful neck, deep chest, and a thick "otter" tail.  The chest should be deep and wide with the ribs well-sprung.  The forelegs should be straight from the shoulder, medium in length and with good bone.  The hindquarters should be very muscular and well developed.  Good angles in the hindquarters is desirable. Overall, the sturdy Labrador should have a balanced, proportional appearance.  

The AKC height standard is 22.5 to 24.5 inches at the withers for males, and 21.5 to 23.5 for females.  The males weigh 66 to 88 lbs. and the females weigh 55 lbs. to 70lbs.  

Visit the AKC website more information