Weight converter
Kilograms, stone, pounds and the rest, all at once. Including both kinds of ton.
Stone, and why it survives
Britain gives body weight in stone and nothing else in stone. Every hospital scale, every gym machine and every food label is metric, and has been for decades.
It survives because it happens to divide the useful range well. Most adults fall between 8 and 20 stone, which are small memorable numbers; the same range in kilograms runs from 50 to 130 and in pounds from 112 to 280. A unit that puts the answer in single or low double digits is easier to carry around.
The two tons, and the one spelt differently
There are three, and they are close enough to be dangerous. A long ton is British, 2,240 lb, about 1,016 kg. A short ton is American, 2,000 lb, about 907 kg. A tonne is metric, exactly 1,000 kg.
A long ton and a tonne are within 2% of each other, close enough that a freight quote can be wrong without looking wrong. When it matters, use the spelling: tonne with the E is always the metric one.
A pound is defined in kilograms
Exactly 0.45359237 kg, by international agreement since 1959. An ounce is a sixteenth of that, and a stone is fourteen pounds.
So the conversions here are exact arithmetic rather than measured approximations, and converting out and back returns precisely the number you started with.
Common questions
- How do I convert kilograms to stone and pounds?
- Divide the kilograms by 6.35029 to get stone, then multiply the decimal part by 14 for the pounds. 70 kg is 11.02 stone, so 11 stone and about 0.3 pounds. The table gives you the stone figure and the pounds figure separately, which is usually easier than working the remainder by hand.
- Why is Britain still using stone?
- Only for body weight, and only in conversation. Every scale in a hospital reads kilograms, every gym machine reads kilograms, and every food label is metric. Stone survives because it splits the useful range into memorable numbers: most adults sit between 8 and 20 stone, where the same range in kilograms is 50 to 130.
- What is the difference between a long ton and a short ton?
- A long ton is the British one, 2,240 pounds or about 1,016 kg. A short ton is American, 2,000 pounds or about 907 kg. A metric tonne is 1,000 kg, which sits between them and is within 2% of the long ton. Shipping and freight quotes are where this catches people.
- Is weight the same as mass?
- Strictly no: mass is how much matter something contains and weight is the force gravity exerts on it, which is why you would weigh less on the Moon while having the same mass. In everyday use the words are interchangeable, and everything on this page converts mass.