Family name ถ้อย (Thoi 
, ถ้อย) , in the world, is quite a rare last name. The last name ถ้อย is characteristic of South-eastern Asia, particularly Singapore, where it is a rare surname, Vietnam, and Malaysia. Measured by absolute frequency, this name is the most popular in India, Vietnam, and Myanmar. Likewise, ถ้อย is the forename as well as the last name.