All over the world, Реико (Reiko 
, Реико 
) is quite a common epicene forename. The first name Реико is characteristic of Japan, where it is quite a rare female name, Hong Kong, and Germany, where it is a rare masculine name. Measured by absolute frequency, it is the most numerous in Japan, the United States, and Brazil. Much less frequently, Реико is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| Reiko | Japan, Germany, China, United States, Brazil |
| Реико | Russia |
Реико is also a name for the fictitious and mythical characters: Reiko Shiratori , the Fictional character of Kamen Rider Black RX; Reiko Katherine Akimoto , the KochiKame characters, Kochira Katsushika-ku Kameari Kōen-mae Hashutsujo; Reiko , character in Mortal Kombat; Reiko , the fictional character from Super Cub and Reiko Nagase , the Fictional video game character, Ridge Racer, among other works.