Weight Converter
Convert between metric and imperial weights, from milligrams to tons. Free, and runs entirely in your browser — nothing you enter is uploaded or stored.
About Weight Converter
Converts a weight between metric units (milligrams, grams, kilograms, tonnes) and imperial and US ones (ounces, pounds, stone, short and long tons). Every unit is shown at once from a single value.
The pound is defined as exactly 0.45359237 kg, and every other imperial unit is built from it, so the conversions are exact. The two kinds of ton are the ones that catch people out: a US short ton is 2,000 lb, a UK long ton 2,240 lb, and a metric tonne 1,000 kg sits between them.
Where it helps
- Metric, imperial and both kinds of ton side by side from one value.
- Exact definitions, so kilograms to pounds and back gives the number you started with.
- Stone is included, which most converters leave out and UK readers need.
- Works for anything from milligrams of medicine to tonnes of freight.
Limits
- Stone and pounds are shown as separate decimals, not as a combined 11 st 2 lb.
- Troy ounces, used for precious metals, are different from these ounces and are not included.
- Cooking measures by volume, such as cups, depend on the ingredient and cannot be converted here.
Frequently asked questions
How many pounds are in a kilogram?
About 2.2046. A pound is defined as exactly 0.45359237 kg, so a kilogram is 1 divided by that.
What is the difference between a ton and a tonne?
A tonne is 1,000 kg. A US short ton is 2,000 lb (907 kg) and a UK long ton 2,240 lb (1,016 kg). All three rows are shown so you can see which one a figure means.
How many pounds are in a stone?
Fourteen. A stone is 6.35 kg, and it is still the usual way to give a person's weight in the UK and Ireland.
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