When it comes to outstanding features, the Chartreux stands alone. They are as strong as their physical appearance indicates. The Chartreux is flexible and agile, with a solid body, strong frame and powerful musculature. The head is broad and rounded, with medium sized rounded ears. The eyes are wide and round, with colours ranging from yellow to orange. The coat is short to medium length, and it is dense, wooly and slightly raised. The colour can be any shade on the grey blue spectrum. The kittens are often born with marbled, striped or small spots on the fur, similar to tabby cat markings. These are called ghost marks, or stripes, and they usually disappear during the first year or two of life. The full, woolly coat appears within to two to three years. This allows them to better withstand extreme cold and harsh winter weather.

At birth, Chartreux kittens weigh from 100 to 120 grams, on average. They tend to double in weight after the first eight days, depending on the milk supply of the mother, and the number of kittens in the litter. At three months the difference between the male and female cats is clearly visible.

The female Chartreux usually weigh between 2.7kg and 6.3kg (6-14 pounds), while the males weight can range from 4.5kg and 9.0kg (10-20 pounds). The male Chartreux cats tend to be slower to mature, taking three to four years to reach full physical maturity. In adulthood, it is not uncommon for female Chartreux to weigh about 2kg less than the male. As with all breeds, the Chartreux kitten will have adult teeth between 4 to 6 months on average. Chartreux usually have a life expectancy of over twelve years.