Weight Converter
Convert a weight between milligrams, grams, kilograms, metric tons, ounces, pounds and stones. The factor line shows the exact number used, so you can redo the arithmetic by hand.
Exact defined factors: 1 lb = 453.59237 g, 1 oz = 28.349523125 g, 1 st = 14 lb.
Formula and calculation
Worked example
A reading of 12 stone is 76.2035 in kilograms. The factor line shows 1 st = 6.350293 kg, so the arithmetic can be checked by hand: 12 × 6.35029 = 76.2035.
Stones, pounds and kilograms in practice
The stone survives in British and Irish body-weight talk: people say they weigh 11 stone rather than 154 pounds or 70 kilograms. Because 1 st = 14 lb exactly, a stone-and-pounds reading is just pounds split on 14, so 11 st 7 lb is 161 lb. Clinics in the UK record kilograms, which is why converting between the two comes up often. For luggage, parcels and shipping, pounds and kilograms are the units that matter; for recipes and small packages, grams and ounces. All of them come from one number worth remembering: 1 kg = 2.20462 lb.
What the results mean
- 1 lb =
- Your value converted to the target unit, using the exact defined factors (1 pound is exactly 453.59237 grams).
- Conversion factor
- The one-way factor for this pair, so you can repeat the arithmetic by hand: value x factor = result.
- Reverse
- The same factor in the opposite direction, for converting a result back later.
Frequently asked questions
How many pounds are in a stone?
Exactly 14, so 12 stone is 168 lb and a person quoted as 11 st 7 lb weighs 161 lb. The stone is still the everyday unit for body weight in the UK and Ireland even though scales there usually show kilograms.
How do I convert kilograms to pounds by hand?
Multiply kilograms by 2.20462262185: a 70 kg adult is 154.32 lb. The factor never changes because the pound is defined as exactly 0.45359237 kg, so no rounding error builds up.
Is a metric ton the same as a US ton?
No. A metric ton (tonne) is exactly 1000 kg, while the US short ton is 2000 lb, about 907.18 kg, and the UK long ton is 2240 lb. The t option here is the metric tonne; freight documents in the US usually mean short tons.
How many grams are in an ounce?
Exactly 28.349523125 g for the avoirdupois ounce used for food, postage and packages. Gold and silver are priced in troy ounces of 31.1034768 g, which is a different unit this converter does not cover.