milligrams

Milligram (abbreviated mg) is a unit of mass in the metric system. It is defined as one thousandth of a gram and one millionth of a kilogram. Since the gram is the base unit of mass in the metric system, the milligram is a derived unit that is typically used for very small masses.

Milligrams are commonly used to quantify masses of substances that are too small to measure effectively in grams. In medicine, pharmacology, nutrition, and chemistry, amounts are routinely expressed in mg. For example, pharmaceutical tablets often contain active ingredients measured in mg. Everyday examples include caffeine in beverages or vitamins and minerals in dietary supplements. In numerical terms, 1 gram equals 1000 milligrams, and 1 milligram equals 0.001 gram; correspondingly, 1 kilogram equals 1,000,000 milligrams, and 1 mg equals 1000 micrograms.

In practice, mg values are measured with balances or analytical scales capable of milligram precision, or with instruments used for weighing liquids and powders. The milligram is an SI-derived unit, and while its use is widespread worldwide, some fields prefer micrograms for extremely small masses.

The term milligram reflects the metric prefixes milli- and gram, and it remains a standard unit for expressing small masses in science, medicine, and nutrition.