The differences between the two breeds include bone structure, body length, and size.
Cardigans are the larger of the two breeds, with large rounded ears and a 12-inch-long (30 cm) fox-like, flowing tail set in line with the body.
Though the Cardigan is allowed more colours than the Pembroke, white should not predominate in its coat.
The Cardigan is a double-coated dog where the outer coat is dense, slightly harsh in texture, and of medium length.
The dog's undercoat is short, soft, and thick.
According to the breed standard, the breed stands between 10.5–12.5 inches (27–32 cm) at the withers, and should weigh between 30–38 pounds (14–17 kg).
The skeletal structure of the Cardigan differs from the Pembroke, in that there is a more exaggerated bend in the front two legs, which fits around the ribcage of the animal.
In addition, the Cardigan is more heavily set than the Pembroke, with denser bone mass.

There are a greater number of colours of coat present in the Cardigan breed than the Pembroke, with the breed standard allowing for a variety of shades of red, sable and brindle.
White markings are expected on this breed of Corgi, and one with a black coat is allowed to have tan or brindle points under conformation show rules.
Merle markings are present in the breed, although this is normally restricted to blue merle.
There are several disqualification criteria in the breed standard for the purpose of conformation showing.
This would include drop ears, a white coat, blue eyes or non-solid black noses in dogs without merle colouration.
The differences between the two breeds include bone structure, body length, and size. Cardigans are the larger of the two breeds, with large rounded ears and a 12-inch-long (30 cm) fox-like, flowing tail set in line with the body. Though the Cardigan is allowed more colours than the Pembroke, white should not predominate in its coat. The Cardigan is a double-coated dog where the outer coat is dense, slightly harsh in texture, and of medium length. The dog's undercoat is short, soft, and thick. According to the breed standard, the breed stands between 10.5–12.5 inches (27–32 cm) at the withers, and should weigh between 30–38 pounds (14–17 kg). The skeletal structure of the Cardigan differs from the Pembroke, in that there is a more exaggerated bend in the front two legs, which fits around the ribcage of the animal. In addition, the Cardigan is more heavily set than the Pembroke, with denser bone mass.
There are a greater number of colours of coat present in the Cardigan breed than the Pembroke, with the breed standard allowing for a variety of shades of red, sable and brindle. White markings are expected on this breed of Corgi, and one with a black coat is allowed to have tan or brindle points under conformation show rules. Merle markings are present in the breed, although this is normally restricted to blue merle. There are several disqualification criteria in the breed standard for the purpose of conformation showing. This would include drop ears, a white coat, blue eyes or non-solid black noses in dogs without merle colouration.
Welsh Corgi