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Convert Stone (ancient) to Kilogram (st (ancient) to kg) 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 (ancient) — a variable historical unit of mass
It was not a single fixed unit; in ancient and medieval use, a “stone” could mean a locally chosen trade weight, often varying by region, period, and commodity. Used historically for weighing goods such as wool, grain, meat, and other trade commodities, and for stone weights used as practical measuring standards.
- Symbol: stone, st
- System: Historical unit for mass; not a fixed SI or modern imperial standard in ancient use
- Common historical range: about 4 to 32 lb ≈ 1.814 to 14.515 kg, depending on context
- Modern reference point: the later British imperial stone is exactly 14 lb = 6.35029318 kg
- Typical examples: trade stones could be used for wool, grain, or livestock products; a “stone” in one market might differ from a “stone” in another; historical records should be interpreted by period and location.
Kilogram (kg) — the SI base unit of mass
It is defined by fixing the Planck constant at exactly 6.62607015×10⁻³⁴ J·s; together with the definitions of the meter and second, this sets the kilogram. Used worldwide for measuring mass in science, engineering, commerce, medicine, food, shipping, and everyday life.
- Symbol: kg
- System: SI base unit for mass
- Exact relations: 1 kg = 1000 g = 1,000,000 mg
- Imperial equivalents (derived from 1 lb = 0.45359237 kg exactly): 1 kg ≈ 2.20462 lb ≈ 35.27396 oz
- Typical examples: 1 liter of water ~1 kg; a laptop ~1.5 kg; an adult person ~70 kg.