What is mass?Mass is a measure of the amount of matter in an object. Mass should not be confused with weight. Weight is the measure of the intensity of the force imposed on this object by gravitational field. Conversion Samples1 kg = 1000 g1 g = 1000 mg1 kg = 2.2046226218 lb1 oz = 28.349523125 g1 lb = 16 oz1 lb = 453592.37 mg