Weight conversion through kilograms
Convert between grams, kilograms, ounces, pounds, stones, US tons and metric tonnes, with the answer in every unit displayed at once. All conversions run through kilograms using the exact international avoirdupois definitions — the pound has been defined as exactly 0.45359237 kg since 1959, so the ounce is exactly 28.349523125 g and the stone exactly 6.35029318 kg (14 pounds). As with the length converter, going through one base unit guarantees every pair of units agrees with every other.
The units, decoded
Three systems overlap here. Metric is decimal and easy (grams → kilograms → tonnes, thousand by thousand). Avoirdupois — the everyday imperial system — runs 16 ounces to the pound and 2,000 pounds to the US short ton. The stone survives mainly in the UK and Ireland for body weight: "11 stone 4" means 11 stone plus 4 pounds, 158 lb in total, and the stats panel shows your weight in that mixed form too. One warning: fluid ounces measure volume, not weight — this converter is strictly about mass, and an ounce of feathers and an ounce of lead both convert identically here.
Body weight, luggage and loads
The usual jobs: a bathroom scale in stones meeting a medical form in kilograms, an airline's 23 kg bag limit against a suitcase weighed in pounds (that is 50.7 lb — the half-pound matters at check-in), or a vehicle's payload in US tons against a spec sheet in tonnes, where the 10% gap between a ton (907 kg) and a tonne (1,000 kg) is the classic expensive misunderstanding. For gold and silver by the troy ounce, use the Gold Calculator, which uses troy weights and prices the metal too.
Worked example
10 kilograms is 22.0462 pounds — also 352.74 ounces, or 1 stone 8.05 pounds in the UK mixed form.
How to use this calculator
- Enter the weight.
- Choose its unit and the unit you want.
- Read the headline answer and the all-units table.
- Check the stats for the mixed forms (pounds-and-ounces, stones-and-pounds).
Ton vs tonne vs long ton
Three "tons" circulate: the US short ton (2,000 lb = 907.185 kg), the metric tonne (1,000 kg), and the old British long ton (2,240 lb = 1,016.05 kg), now rare outside shipping history. This converter includes the first two. When a document just says "tons", context decides — American sources mean short tons, international and scientific sources usually mean tonnes.
Converting one specific pair? These single-pair pages are pre-set and carry a full table for that pair: Kg to Lbs, Lbs to Kg, Grams to Ounces and Ounces to Grams.