Since the kilogram is the bigger of the two units, 1 gram is equal to 0.001 kilograms. However, there are 1,000 grams in a kilogram. Both units are metric measurements used to define the mass of an object.
The kilogram is the SI base unit for mass, and from it, other SI units such as the gram and milligram are derived. A gram is equal to 1,000 milligrams. The SI symbol for the kilogram is "kg," while the symbol for the gram is "g."
According to the National Institute of Standards and Technology, the kilogram is defined by the mass of a platinum-iridium standard that is kept at the International Bureau of Weights and Measures.