The service determines the placename in Japan specified by location parameters such as latitude and longitude. Place specifications documented include the location's prefecture, municipality, and "Aza" or section. Only the Japanese language is supported.
API methods support specification of a location by latitude and longitude, with an optional radius defining an area around the designated point. Separate radius parameters may be entered for street address and "Aza" (section) designation. Methods return named prefecture, municipality, and local values such as street address, along with Aza.