Cognomen นิจิ (Niichi 
, Nichi 
, นิจิ 
) , in the world, is a rare family name. The surname นิจิ is habitual in Panama, where it is a rare surname, Romania, and Chile. Measured by absolute frequency, it is the most numerous in Indonesia, Thailand, and Brazil. Much more prevalently, นิจิ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Niichi | Brazil, United States, Japan |
| Nichi | Romania, Brazil, India, Indonesia, Japan |
| นิจิ | Thailand |
| Nijy | India |