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Convert Gram to Carat (g to ct) 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.
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.