Difference Between Koi and Carp

Koi vs Carp

Koi and carp are very closely related fish types, yet they are sometimes considered as different types of the same species. However, there are important facts to consider about both Koi and carp before classifying them in the same group or into different groups. Hence, it would be highly interesting to know the characteristics and the differences between Koi and carp.


Koi is an ornamental variety of common carp, Cyprinus carpio. They have stout and elongated bodies, and their fins are short but full of colours. They have distinctive and colourful body patches those make Koi fish attractive. Usually, Koi fish are preferred in outdoor ponds or water gardens. They have a range of colours including white, black, red, yellow, blue, and cream. The special feature about Koi fish is that they do not have varying body shapes across their breeds, but coloration and scalation could be different among them. Koi fish has two small whisker-like sensory organs hanging in their mouth known as barbels. Japanese started to breed Koi as an ornamental fish in the early 19th century from a common carp.


Carp or the common carp, Cyprinus carpio, is predominantly a freshwater bony fish species, but very few of their relatives live in seawater. However, it should not count only the common carp when the carps are considered, as all the members of the Family: Cyprinidae are referred with the same name. It would also be important to know that some scientists refer only to the large-bodied cyprinids as carps (Common carp, Bighead carp, Crucian carp, Grass carp, Mrigal carp, Black carp, Catla carp, Mud carp, and Silver carp). Therefore, it becomes clear that the term carp has been used variably in different places.

None of the carp genera except Tribolodon could live in the sea, but there are many species with the capability to live in brackish water. However, the vast majority of them are found in the freshwater including the common carp. The importance of carps has been immense for humans in many ways such as being a protein source (food), as well as an ornamental fish. In fact, common carp is one of the most important ornamental fish species that has been developed into multi coloured Koi fish varieties. Additionally, the popular goldfish has been developed from a carp species, Carassius gibelio. It would also be important to state that there is a total production of over 24 million tonnes of carps in 2010 for food.

What is the difference between Koi and Carp?

• Koi is an ornamental fish of the species common carp. On the other hand, carp is usually the group of cyprinids, but sometimes considered either as large-bodied cyprinids or just the common carp. This means that the scope is much more diversified for carps than for Koi fish.

• Koi is an ornamental fish, but carps are either ornamental or food fishes.

• Koi belong to only one species, whereas carps are of many different species.

• Koi lives in freshwater, but there is one genera (few species) of carps found in the sea.

• Koi are raised and maintained in rather artificial tanks than in wild, which is highly comparable with wild carp species.