As a Chinese surname, Chin could originate from numerous Chinese characters including the following, listed by their spelling in Mandarin Pinyin:[1] As a Korean surname, Chin is the McCune–Reischauer romanisation of the four surnames more commonly spelled Jin in the Revised Romanization of Korean (Korean: 진; Hanja: 陳, 秦, 眞, or 晉; IPA: /t͡ɕin/).
There is no modern Korean surname which Revised Romanization would spell as Chin (친).
[1] The 2010 United States Census found 27,487 people with the surname Chin, making it the 1,279th-most-common name overall.
This represented an increase in absolute numbers, but a decrease in relative frequency, from 25,673 (1,255th-most-common) in the 2000 Census.
In both censuses, slightly more than three quarters of the bearers of the surname identified as Asian, about 6% as White, and about 6% as Black.