Calico vs tortoiseshell: how to tell them apart

Calico vs tortoiseshell comes down to one thing: white. A tortoiseshell cat, or tortie, has black and orange mixed together with little or no white. A calico has the same black and orange, plus clear patches of white, which is why calicos are also called tortoiseshell and white. Both coats come from the same genes on the X chromosome, and that is why both are almost always female. Below, how to tell them apart, why the colours land where they do, and where you will find both in our Find your cat designs.

Calico vs tortoiseshell at a glance

• Tortoiseshell: black (or its paler form, grey) and orange mixed through each other, often finely brindled, sometimes in larger blotches. Little or no white.
• Calico: white, orange and black in distinct patches. The more white the cat has, the larger and cleaner the coloured patches tend to be.
• Dilute versions: when the colours are softened, black becomes grey, giving a dilute tortie or a dilute calico.
• With stripes: either coat can carry tabby markings too.

Why the colours come in patches

In cats, the gene that decides between black and orange pigment sits on the X chromosome. A female has two X chromosomes, so she can carry the orange version on one and the black version on the other. Early in development, each of her cells switches off one X at random, and every cell that descends from it keeps the same choice. The result is a coat of patches, some from cells showing orange and some from cells showing black. Because the choice is random, no two torties or calicos look alike: even a cloned calico, a famous case from 2002, did not match the cat she was cloned from.

Where the white comes from

The white of a calico is not part of the X chromosome story. It comes from a separate white spotting gene that keeps pigment cells from reaching parts of the skin as the kitten develops. Those areas grow white fur, and the orange and black are pushed into separate islands. That is why a calico’s colours look tidier than a tortie’s: the white breaks the coat up into patches.

Can a calico or tortie be male?

Very rarely. A male usually has one X and one Y, so he can show orange or black, but not both. A male calico or tortie normally has an extra X chromosome (XXY). Vets quote a University of Missouri study that found only one in every 3,000 calico cats is male, and these males are usually unable to father kittens.

Tortie personality

Owners often talk about “tortitude”, the idea that torties are sassy and strong-willed. It is a friendly bit of folklore rather than science: a cat’s character comes from its upbringing and its own nature, not from the colour of its coat. Our tortie, we admit, has opinions.

One coat, several names

The names change from place to place. Calico is the usual word in American English; elsewhere the same cat is often called a tortoiseshell and white, or simply a tricolour. Tortie is the friendly short form of tortoiseshell. Neither is a breed: both coats appear in many breeds and in mixed-breed cats.

Telling them apart at home

Look first for white. If there are large, clear white areas, usually on the chest, belly and paws, you have a calico. If the coat is mostly black and orange mingled, with at most a few white hairs or a small white spot, you have a tortie. Then look at how the colours meet: in a calico they sit in separate islands, in a tortie they run into each other.

Calico and tortie, embroidered

Both coats are in Find your cat. The Calico is curled into a loaf, white with patches of orange and black, in three thread colours. The Tortie is black with orange running through it and half her head in ginger. Each is machine embroidered at the centre of the chest of a heavyweight cotton tee, a fleece crewneck or a hoodie, or on the front of a cotton tote, and made for you after you order. For the full family of coats, from tabby to tuxedo, read our guide to cat coat patterns.

Which piece to choose

Each design comes on four pieces. The heavyweight tee is 100% ring-spun cotton, garment-dyed, in sizes S to 4XL. The crewneck and the hoodie are a soft fleece of cotton with some polyester, in sizes S to 3XL. All three are a relaxed fit, so order your usual size, and the size guide lists every measurement in centimetres. The tote is one size, 38 × 42 cm. The Calico garments come in pepper or blue jean, with a French navy tote; the Tortie comes in white or seafoam, with a natural tote. Every piece is made for you after you order, and each product page shows the expected delivery dates, with free tracked shipping.

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