The milligram (mg) is a tiny metric unit of mass equal to one-thousandth of a gram, essential in pharmaceuticals and nutrition labeling. Medication dosages, vitamin content, and food additive quantities are typically expressed in milligrams. One milligram equals approximately 0.0000353 ounces, making it the go-to unit for measuring extremely small masses.

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.