Select a category
Conversion Formula:
Convert Gram to Milligram (g to mg) instantly with accurate, readable results.
Use our Mass Unit Converter to convert between grams, kilograms, pounds, ounces, and other weight units instantly. Designed for cooking, science, fitness, and engineering needs, this unit conversion tool offers accurate results between metric and imperial systems. Whether you’re tracking body weight, measuring ingredients, or handling heavy machinery, our mass unit conversion calculator has you covered.
Gram (g) — a common SI unit of mass
It is defined as one thousandth of a kilogram, the SI base unit for mass; the kilogram is defined by fixing the Planck constant at exactly 6.62607015×10⁻³⁴ J·s. Used worldwide for measuring small amounts of mass in science, cooking, nutrition, medicine, commerce, and everyday life.
- Symbol: g
- System: SI unit for mass; decimal submultiple of the kilogram
- Exact relations: 1 g = 0.001 kg = 1000 mg
- Imperial equivalents (derived from 1 lb = 0.45359237 kg exactly): 1 g ≈ 0.03527396 oz ≈ 0.00220462 lb
- Typical examples: a paperclip ~1 g; a teaspoon of sugar ~4 g; a chocolate bar ~50 g.
Milligram (mg) — a small SI unit of mass
It is defined as one thousandth of a gram, or one millionth of a kilogram, the SI base unit for mass. Used worldwide for measuring very small masses in medicine, nutrition, chemistry, laboratory work, supplements, and precise product labeling.
- Symbol: mg
- System: SI unit for mass; decimal submultiple of the kilogram
- Exact relations: 1 mg = 0.001 g = 0.000001 kg = 1000 µg
- Imperial equivalents (derived from 1 lb = 0.45359237 kg exactly): 1 mg ≈ 0.000035274 oz ≈ 0.00000220462 lb
- Typical examples: a medicine dose ~200 mg; a vitamin tablet ~500 mg; a small grain of salt less than 1 mg.