Cognomen Keiichi (Keiichi 
, ケイイチ , Кеиичи 
) , worldwide, is a common surname. The last name Keiichi is characteristic of Eastern Asia, particularly Japan, where it is quite a common surname, Taiwan, where it is quite a rare surname, and Hong Kong, where it is a rare surname. Measured by absolute frequency, it is commonest in Eastern Asia, particularly Japan, China, and Taiwan. Much less frequently, Keiichi is the forename as well as the last name.