The ranchu is similar to the lionhead but has a much more curved posterior dorsal contour, making an acute angle of join (less than 90 degrees) with the upper lobe of the tail fin at the caudal peduncle, whereas in the lionhead the dorsal contour is flatter and the angle of join is obtuse (more than 90 degrees); also, the ranchu tail is splayed sideways with the lower lobes sometimes lying almost horizontal, whereas the lionhead tail is like that of the fantail. Calico ranchus seem to be favoured over self-coloured fish, whereas more metallic (particularly red) lionheads are seen than calico. The ranchu was developed in China and imported and further developed in Japan.

Ranchu are also known in the Far East as buffalo-heads. Calico ranchu are known as edonishiki in Japan.