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Convert Carat to Stone (ct to st) 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.
Carat (ct) — a metric unit of mass for gemstones
It is defined as exactly 200 milligrams, or one fifth of a gram. Used worldwide for measuring diamonds, gemstones, pearls, and other jewels; it should not be confused with karat, which measures gold purity.
- Symbol: ct
- System: Non-SI metric unit for mass; used with SI
- Exact relations: 1 ct = 200 mg = 0.2 g = 0.0002 kg
- Imperial equivalents (derived from 1 lb = 0.45359237 kg exactly): 1 ct ≈ 0.00705479 oz ≈ 0.000440925 lb
- Typical examples: a small diamond ~0.25 ct; an engagement-ring diamond ~1 ct; large gemstones may be several ct.
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.