Convert Kilogram (kg) to Hundredweight (UK) (cwt (UK)) instantly.
About these units
Kilogram (kg)
The kilogram is the base unit of mass in the SI system and the only SI unit defined directly by a fundamental constant rather than a physical object. Originally, its definition was tied to a platinum–iridium artifact stored in France—the famous "International Prototype Kilogram." Over time, tiny mass changes in the prototype and its official copies created difficulties for high-precision science. In 2019, the kilogram was redefined using Planck's constant, linking mass to the laws of quantum physics through the Kibble balance. This innovation ensures universality, stability, and reproducibility across the world. The kilogram is central to commerce, science, engineering, and every quantitative field dealing with matter. Its decimal relationships with other metric units (grams, milligrams, tons) make it universally convenient. From groceries to spacecraft mass budgets, the kilogram anchors modern mass measurement.
Hundredweight (UK) (cwt (UK))
The British hundredweight equals 112 pounds (50.802345 kg). The extra 12 pounds derive from England's historical use of a 14-pound stone. The British hundredweight was used across the former British Empire for trade, taxation, and freight classification. It scales into the long ton (20 cwt = 1 long ton), forming a fully coherent system within imperial measurements. While replaced by metric units in the UK, this unit persists in historical documents, trade archives, and older engineering references.