Weight Converter
Convert mg, grams, kilograms, tonnes, ounces, pounds, stone and US tons.
Quick answer
- Formula: Result = Value × (factor of from-unit in kg) ÷ (factor of to-unit in kg)
- Worked example — Converted weight: 0.453592 (full example below).
Weight Converter
| Converted weight | 0.453592 |
| Summary | 1 lb = 0.453592 kg |
One pound is exactly 0.45359237 kg — so a 180 lb person weighs about 81.6 kg.
Convert mass between metric and imperial units through the kilogram. The international pound is defined as exactly 0.45359237 kg, so 1 ounce is exactly 28.349523125 g, 1 stone is exactly 14 lb (6.35029318 kg) and a US short ton is exactly 2000 lb (907.18474 kg).
Note the traps: a US ton (2000 lb) is lighter than a metric tonne (1000 kg ≈ 2204.6 lb), and a British long ton (2240 lb) is different again — this converter uses the US short ton.
The formula
Worked example
One pound is exactly 0.45359237 kg — so a 180 lb person weighs about 81.6 kg.
The example is pre-loaded in the result panel — press Calculate with your own numbers to replace it.
Frequently asked questions
How many pounds are in a stone?
Exactly 14 pounds. Stone is still commonly used for body weight in the UK and Ireland; 10 stone is 140 lb or about 63.5 kg.
Is a ton the same as a tonne?
No. A US short ton is 2000 lb (907.18 kg), a metric tonne is 1000 kg, and a British long ton is 2240 lb (1016 kg).
How many ounces are in a pound?
Exactly 16 avoirdupois ounces. (Troy ounces, used for precious metals, are heavier and divide a troy pound into 12.)
Category: Unit Conversions calculators
Sources & methodology
This calculator applies the formula shown on this page exactly as written, using the standard definitions for its inputs. Results are computed from the values you enter — no data is stored — and are rounded only for display.
Content last reviewed by CalcHub Editorial.
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