The kilogram (kg) is the base unit of mass in the International System of Units, defined by the Planck constant since 2019. It is the most widely used mass unit globally for body weight, grocery items, and shipping, appearing on scales in homes and markets everywhere. One kilogram equals roughly 2.2046 pounds.

The jin (斤) is a traditional Chinese unit of weight equal to 500 grams, or exactly half a kilogram. It remains the most common weight unit in Chinese markets, groceries, and daily life, where vegetables, meat, and fruit are sold by the jin. One jin equals 1.1023 pounds or exactly 500 grams.