mass · International gemstone trade · Modern standardized

metric carat

exact

Definition

1 metric carat = exactly 200 mg = 0.2 g.

One metric carat is exactly 0.0002 kilograms.

Carat derives from historical seed-based weighing traditions; the modern metric carat was standardized at 200 mg in the early 20th century.

Modern use is context-dependent and varies by region or measurement system.

Source tier — · confidence high

mass · International · Modern

1 g = 0.001 kg.

mass · International · Modern

SI base unit of mass. The Planck constant is fixed exactly at 6.62607015×10^-34 J·s, which defines the kilogram through the metre and second.

mass · International · Modern

1 tonne = 1000 kg.

mass · UK / US · Modern / historical

1 avoirdupois ounce = exactly 1/16 international pound = 0.028349523125 kg.

mass · UK / US · Modern / historical

1 international avoirdupois pound = exactly 0.45359237 kg.

mass · UK / US · Modern / historical

1 stone = 14 lb = exactly 6.35029318 kg using the international pound.

Da; u

mass · International · Modern

Dalton/u is 1/12 of the mass of a free carbon-12 atom in its ground state. CODATA 2022: 1.66053906892(52)×10^-27 kg.

approx.

mass · Ancient Greece / Rome · Antiquity

Greek talent was not one universal standard.

variant