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Conversion Formula:
Convert Stone to Milligram (st 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.
Stone (st) — an imperial unit of mass equal to 14 pounds
It is defined as exactly 14 avoirdupois pounds; since 1 lb = 0.45359237 kg exactly, 1 st = 6.35029318 kg exactly. Used mainly in the United Kingdom and Ireland for measuring human body weight.
- Symbol: st
- System: Imperial unit for mass
- Exact relations: 1 st = 14 lb = 224 oz = 6.35029318 kg
- Metric equivalents: 1 st ≈ 6.35029 kg ≈ 6350.29 g
- Typical examples: a person weighing 10 st is 140 lb; a small adult ~8 st; a larger adult ~15 st.
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.