White chocolate: 200 ounces per pound of body weight. It takes 250 pounds of white chocolate to cause signs of poisoning in a 20-pound dog, 125 pounds for a 10-pound dog.
Milk chocolate: 1 ounce per pound of body weight. Approximately one pound of milk chocolate is poisonous to a 20-pound dog; one-half pound for a 10-pound dog. The average chocolate bar contains 2 to 3 ounces of milk chocolate. It would take 2-3 candy bars to poison a 10 pound dog. Semi-sweet chocolate has a similar toxic level.
Sweet cocoa: 0.3 ounces per pound of body weight. One-third of a pound of sweet cocoa is toxic to a 20-pound dog; 1/6 pound for a 10-pound dog.
Baking chocolate: 0.1 ounce per pound body weight. Two one-ounce squares of bakers' chocolate is toxic to a 20-pound dog; one ounce for a 10-pound dog.