Last name Окамото (Okamoto 
, Kazumitsu 
, Neiho 
) , worldwide, is quite a common cognomen. The cognomen Окамото is characteristic of Japan, where it is quite a rare surname, Singapore, and Brazil. In absolute terms, the name is most common in Brazil, Japan, and the United States. Much less frequently, Окамото is the forename as well as the last name.