What is a kilogram?
A kilogram is metric unit of weight subdivided into 1,000 grams. The base unit of mass in the International System of Units (SI) is a kilogram and not, as is quite often mistaken, the gram.
One liter of water weighs 1kg.
What is a gram?
A gram is a unit of mass in the metric system, equal to one thousandth of a kilogram. It is commonly used to measure small amounts of mass, such as the weight of food ingredients, jewelry, or medication. The gram is represented by the symbol "g" and is a fundamental unit in the International System of Units (SI).