How this calculator works
The stone is a British customary unit of mass fixed at exactly 14 pounds. With the international pound of 0.45359237 kg, one stone is 6.35029318 kg. Body weight in the United Kingdom and Ireland is often given as stones and pounds, while most other countries use kilograms. The conversion is an exact division by the stone factor. If a result such as 11.0231 st looks awkward, multiply the part after the decimal point by 14 to get the extra pounds.
Formula
st = kg / 6.35029318. kg = st x 6.35029318. One stone is 14 lb and one pound is 0.45359237 kg, so 14 x 0.45359237 = 6.35029318 kg.
Worked example
70 kg = 11.0231 st, or 11 st 0.32 lb. 80 kg = 12.5978 st. 100 kg = 15.7473 st. 1 st = 6.35029 kg. 14 lb = 1 st.
Advertisement
Frequently asked questions
How do I read 11.0231 stones in stones and pounds?
The whole number is 11 stones. Multiply 0.0231 by 14 to get 0.323 pounds, so 70 kg is about 11 st 0.3 lb. For a body weight there is no need for more than one decimal place of stone.
Why is 14 pounds one stone?
The stone is a traditional British wool and trade unit that was standardised at 14 pounds. It is not part of the SI, but it remains in common use for body weight in the United Kingdom and Ireland.
Is a stone a mass or a weight?
Technically it is a mass, like the kilogram and pound. In everyday use people say weight, and the conversion is the same everywhere on Earth for practical purposes.
Can I convert pounds directly?
Yes. Choose pounds as the source unit on this page. The result is then shown in stones and in kilograms, and the pound to stone page performs the same conversion from the other direction.