What Is a Stone? The British Weight Measurement Explained
Understand the stone measurement system still used in the UK and Ireland, and how it relates to pounds and kilograms.
Use the Stone ↔ Kilograms
Convert between stone and kilograms
What Is a Stone
A stone is a unit of weight equal to 14 pounds, which works out to approximately 6.35 kilograms. It is used primarily in the United Kingdom and Ireland to express body weight in everyday conversation. The stone has been used in British trade since at least the 14th century, when it was originally used for weighing agricultural goods. Its value varied by region and commodity before being standardized at 14 pounds in 1835 by the Weights and Measures Act.
Converting Stone to Other Units
Converting between stone and other weight units is straightforward.
Where the Stone Is Used Today
The stone is used almost exclusively in the United Kingdom and Ireland, and even within those countries, its use is primarily limited to expressing personal body weight. If you ask someone in London how much they weigh, they will almost certainly answer in stone and pounds rather than kilograms. However, younger generations in the UK are increasingly comfortable using kilograms. Hospitals, doctors, and all medical contexts in the UK use kilograms for precision and international consistency. You will never encounter the stone in scientific work, international commerce, or outside the British Isles. Australia used the stone until the 1960s when the country officially switched to the metric system, and it has essentially disappeared from everyday use there.
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