Surname さえき (Saeki 
, さえき) , in the entire world, is quite a rare last name. The family name さえき is habitual in Hong Kong, where it is quite a rare surname, Taiwan, where it is a rare surname, and Singapore. Not in comparison with a country's population, it is the most numerous in Japan, Brazil, and Taiwan. Very seldom, さえき is the forename as well as the last name.