Every cat is adorable, but sometimes it can be hard to know one breed from another — especially in the case of look-alike cats. How can you tell if you’re looking at a Russian Blue or a Korat? A Siamese or an Oriental Shorthair? Vetstreet can help: Click through the gallery for a look at some “twin” breeds and their sometimes subtle differences.

Korat and Russian Blue

Korat and Russian Blue

The Russian Blue (left) and Korat both sport a short, silvery blue coat and green eyes, but if you look closely, you can tell which is which. Both have large, round eyes, but when partially or fully closed, the Korat’s eyes generally have a slanted appearance. Interestingly, the brilliant green color doesn’t appear until the Korat is 2 to 4 years old. Before then, the eyes are yellow, amber or amber-green. A Russian Blue’s ears are typically more pointed at the tips and set to the side of the head, while a Korat’s have a rounded tip and are set high on the head. The Korat’s head tends to be heart-shaped, and the Russian Blue’s is triangular, or wedge-shaped. Their coats are different, too. The Russian Blue has a dense double coat — ideal for those cold Russian winters, no doubt — while the Korat, who hails from tropical Thailand, has a single coat. Finally, body type sets them apart. The Russian Blue is generally fine-boned, long and muscular; the Korat is broad-chested and muscular, a body type called semi-cobby.
British Shorthair and Chartreux

British Shorthair and Chartreux

The British Shorthair (left) comes in many different colors and patterns, but the blue variety is most popular — in fact, those cats are often described as “British Blues,” as if they were a separate breed (they’re not). His French cousin, the Chartreux, comes solely in shades of blue gray, ranging from ash to slate. Both have bodies that could best be described as, well, chunky. The Chartreux’s legs are generally more slender than the British Shorthair’s, but both have rounded paws. A British Shorthair has a short, dense, single coat that never has a woolly texture. The Chartreux’s coat is just the opposite: a medium-short double coat with a slightly woolly texture. Their ears are different as well: A British Shorthair’s tend to be set far apart, while a Chartreux’s are set high on the head. Chartreuxs are known for their copper-to-gold-colored eyes, and blue British Shorthairs also have gold- or copper-colored eyes.
Siamese and Oriental Shorthair

Siamese and Oriental Shorthair

The Siamese (left) is the parent to several different breeds, one of them being the Oriental Shorthair. Both breeds usually have long, slender bodies and short hair, and they tend to have the same great personality: talkative, intelligent and curious — some would say to a fault. Where they differ is coat pattern. The Siamese has a pointed coat: a pale body with dark points on the feet, face, ears and tail. The point colors are seal, blue, chocolate or lilac. That's it. The Oriental comes in a whopping 350-plus color and pattern combinations, including solids, tabbies, tortoiseshells, silvers, particolors and bicolors, as well as traditional point colors plus some more exotic ones such as tortie smoke and cinnamon lynx.
Maine Coon and Norwegian Forest Cat

Maine Coon and Norwegian Forest Cat

The most notable shared characteristic of the Maine Coon (left) and Norwegian Forest Cat (or NFC) is their immense size. At first glance, these long-haired, silky-coated felines bear a strong resemblance to each other, but they do have some distinct differences. Starting at the top, the NFC’s head is typically triangular with a flat forehead, straight nose profile and medium-size to large ears that are rounded at the tip. The Maine Coon’s head tends to be slightly longer than it is wide — often described as wedge-shaped — with high cheekbones, a squarish muzzle, a slightly concave nose profile, and large well-tufted ears that are wide at the base and taper to a point. Looking at the coat, the NFC’s double coat is long and smooth, while the Maine Coon usually has a heavy and shaggier appearance. Maine Coons tend to be larger; the NFC often has a more compact body. Overall, when you look at a Maine Coon, you should see squares, rather than the triangles that characterize the NFC.
American Shorthair and Domestic Shorthair

American Shorthair and Domestic Shorthair

You might think these two cats are interchangeable, but one is pedigreed while the other is random-bred. How does that make them different? The American Shorthair (left) has a specific look that is easily reproduced. He’s defined by circles. An American Shorthair generally has a large, rounded head with a square muzzle and ears with slightly rounded tips, rounded paws and a compact body. A domestic shorthair might have some of those characteristics, but because he’s a jumble of genes, he might also have the wedge-shaped head of a Siamese or a rangier body type or any of a number of other differences.

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