Surname หนูน้อย (Nunoi 
, Ratkai 
, Ratnoi 
) , in the world, is quite a rare last name. The surname หนูน้อย is characteristic of Hungary, where it is quite a common surname, Slovenia, where it is quite a rare surname, and Japan. In absolute terms, it most frequently occurs in Japan, Hungary, and Thailand. Very seldom, หนูน้อย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Nunoi | Japan, China, Thailand, Canada, Brazil |
| Ratkai | Germany, Hungary, United States, Canada, Slovenia |
| Ratnoi | India, Thailand |
Hnoomai, Hnoonoi, Nhooknao, Nhoonid, Nhunoi, Noannoi, Noanyai, Noikhoa, Noikhog, Noinachom, Noinao, Noinuay, Noiphoem, Nomnoy, Noochnoi, Noochnum, Noochoom, Noochoui, Noochoy, Noojeak, Nookiaw, Nooleung, Noomaung, Noonaiw, Noopheak, Nootnoi, Noottnaom, Nootyong, Noouang, Nooyoi, Noungnoi, Nuchauy, Nukhioa, Numanoi, Numeanug, Nunainum, Nunnoiy, Nuphoi, Nusain, Nuynoi, Ratanyoo, Ratboonno, Ratborworn, Ratbowon, Ratcatnat, Ratnoomnoi, Ratnoy, and Ratsamoot