About the Weight Converter
This weight converter (strictly, a mass converter) switches between 11 units: milligrams, grams, kilograms and metric tons; ounces, pounds and stone; US short tons and UK long tons; plus troy ounces for precious metals and carats for gemstones. Choose your starting and target units and the table shows the same weight in all of them.
It is built for everyday jobs — body weight in kg, lbs or stone, recipe quantities, luggage allowances, parcel and freight weights, gym plates, and gold or jewelry weights. Body weight is also shown in the UK stone-and-pounds format (for example 10 st 10 lb), which most converters leave out.
Every factor is exact: the international avoirdupois pound is defined as 0.45359237 kg, an ounce is 1/16 lb, a stone is 14 lb and a troy ounce is 31.1034768 g.
With the default inputs, the converted weight is 68.0389. Change any value above to recalculate instantly.
How to use the weight converter
- 1Enter the weight you want to convert.
- 2Choose its unit under “From”.
- 3Choose the unit you want under “To”.
- 4Read the result; body weight is also shown in stone and pounds.
- 5Use the table to see the same weight in every other unit.
Formula and method
Each unit is stored as its exact mass in grams. The value is converted to grams and then to the target unit. The avoirdupois pound is exactly 453.59237 g (so 1 kg ≈ 2.20462 lb), an ounce is 1/16 lb (28.349523125 g) and a stone is 14 lb (6.35029318 kg).
A US short ton is 2,000 lb, a UK long ton 2,240 lb and a metric ton (tonne) 1,000 kg. Troy ounces (31.1034768 g) are used only for precious metals and carats (0.2 g) for gemstones. The stone-and-pounds display rounds pounds to one decimal and carries a full 14 lb into the next stone.
- lb
- Avoirdupois pound = 453.59237 g
- oz
- Avoirdupois ounce = 1/16 lb
- st
- Stone = 14 lb
Worked examples
150 lb body weight to kilograms
150 × 0.45359237 = 68.04 kg. Dividing 150 lb by 14 gives 10 stone with 10 lb left over.
70 kg to pounds
70 ÷ 0.45359237 = 154.32 lb, or 2,469 ounces.
12 stone to kilograms
12 stone is 12 × 14 = 168 lb, and 168 × 0.45359237 = 76.20 kg.
1 kilogram to ounces
1,000 g ÷ 28.349523125 g per ounce = 35.27 oz, which is 2.2046 lb.
Frequently asked questions
How do I convert pounds to kilograms?+
Multiply pounds by 0.45359237 (or divide by 2.20462). For example, 200 lb × 0.4536 = 90.72 kg. A mental shortcut is to halve the pounds and subtract 10%.
How many pounds are in a stone?+
One stone is exactly 14 pounds, or 6.35 kg. Stone is still used for body weight in the UK and Ireland, so 11 st 4 lb means 158 lb or 71.7 kg.
What is the difference between a ton and a tonne?+
A US short ton is 2,000 lb (907.2 kg), a UK long ton is 2,240 lb (1,016 kg), and a metric tonne is 1,000 kg (2,204.6 lb).
Is a troy ounce heavier than a regular ounce?+
Yes. A troy ounce used for gold and silver is 31.1035 g, about 10% heavier than the everyday avoirdupois ounce of 28.3495 g.
Is weight the same as mass?+
Strictly, kilograms and pounds measure mass, while weight is a force. In everyday use on Earth the terms are interchangeable, and scales display mass units.