The Chartreux is a rare breed of cat from France, and is recognised by a number of registries around the world. The Chartreux is large and muscular (called cobby) with relatively short, fine-boned limbs, and very fast reflexes. They are known for their blue (silver-grey) water-resistant short hair double coats which are often slightly thick in texture (often showing "breaks" like a sheepskin) and orange or copper-coloured eyes. Chartreux cats are also known for their "smile"; due to the structure of their heads and their tapered muzzles, they often appear to be smiling. Chartreux are exceptional hunters and are highly prized by farmers.

As for every French cat with a pedigree, the first letter of the official name of a Chartreux cat encodes the year of its birth.^[1] All Chartreux born in the same year have official names beginning with the same letter. The code letters rotate through the alphabet each year, omitting the letters K, Q, W, X, Y, and Z. For example, a Chartreux born in 2021 would have an official name starting with the letter S.^[2]