Li (), called lei in Cantonese, ly in Vietnamese or "cash" in English, is a traditional Chinese unit for weight measurement. It originated in China before being introduced to neighboring countries in East Asia. Nowaday, the mass of 1 li equals 50 mg (i.e., 0.05 grams) in mainland China, 37.5 mg in Taiwan, 37.8 mg in Hong Kong, Singapore and Malaysia, and 37.8 mg in Vietnam. Li is mostly used in the traditional markets.
On June 25, 1959, the State Council of the People's Republic of China issued the "Order on the Unified Measurement System", retaining the market measure system, with minor amendment.
where 1 li equals 50 mg or 0.05 grams, and 10 li equals 1 fen.
The Taiwanese still use the old weights and measures of the Chinese Qing Dynasty. 1 Taiwan li is equal to 37.5 mg, or 1/10 Taiwan fen.
In Hong Kong, one li is equal to 1/10 fen, which is 37.799 mg or 0.037799 grams.
Singapore and Malaysia have similar regulations as Hong Kong, as they are all former British colonies.
In Vietnam, 1 li or ly is equal to 37.8 mg (i.e., 0.038 grams) or 1/10 fen by traditional value.
For more information on the Chinese mass measurement system, please see article Jin (mass).