Check out Body Condition Score charts. Some use a scale of 1-5, but I prefer looking at the ones that range from 1-9. Some even differentiate between small, medium, large, and giant breed dogs. Royal Canin Body Score Condition Charts. On a scale of 1-9, dog should be at a 4 or 5 depending on breed, age, and lifestyle. Many dogs I see in my area are at least a 7, and many pet owners that don’t know any better believe a 6 (overweight) or a 7 (obese) is what they are supposed to look like. When they see a young, fit dog at a 4, they assume the dog is being starved. Remember that diet is only one part. To help strengthen and build muscle that will help burn fat and keep it off, exercise is just as crucial. If you can swing it, swimming is a phenomenal way to exercise overweight dogs since there’s little impact on their joints.