Kilograms to pounds – and pounds to kilograms

Formula

Multiply the value in kilograms by 2.2046226 to get pounds.
lb = kg × 2.2046226

Multiply the value in pounds by 0.45359237 to get kilograms.
kg = lb × 0.45359237

How to convert kilograms to pounds

Type a value in the field above and the result is calculated instantly. Use the arrow button to swap direction, or pick other units from the lists.

Doing it in your head

A rough conversion for when the calculator is not to hand. The error comes last, and it holds in both directions at that order of magnitude.

• Kilograms to pounds: × 2 + 10%. That gives 2.2 instead of 2.20462, an error of 0.21%.
• Pounds to kilograms: ÷ 2 − 10%. That gives 0.45 instead of 0.453592, an error of 0.79%.

About the units

Kilograms. The kilogram is the SI base unit of mass, fixed since 2019 by a defined value for the Planck constant, 6.62607015 × 10⁻³⁴ J s. Before that it was a platinum-iridium cylinder in Paris, sanctioned in 1889 and dropped as the definition in 2018. It is a legal unit across the EU, and US consumer packaging must carry a metric quantity too. A litre of water weighs almost exactly a kilogram. Mass is not weight, and the kilogram is the only base unit whose name carries a prefix.

Pounds. A pound has been exactly 0.45359237 kilograms since 1 July 1959, settled jointly by six countries and written into both US and British law. It divides into 16 ounces. It is the general unit for weight and body weight in the US, where adult men average 199 pounds, while in the EU and the UK it may only be a supplementary indication. Do not confuse the pound as a mass with pound-force, nor with the German Pfund, which in everyday use is 500 grams.