Convert Kilograms to Pounds

About converting Kilograms to Pounds

Kilograms (kg) and Pounds (lb) are both units of weight & mass, so converting between them is a single multiplication: multiply your Kilograms figure by 2.2046. Ten Kilograms comes to 22.0462 Pounds, and a hundred works out at 220.4623 Pounds.

Rule of thumb: going from Kilograms to Pounds multiplies, so the figure always grows — one Kilogram is already 2.2046 Pounds. If your answer came out smaller, you have the conversion the wrong way round.

What is a Kilogram?

The kilogram was the last SI unit still defined by a physical object — the International Prototype Kilogram, a platinum-iridium cylinder kept in a vault near Paris since 1889. The problem was that it drifted. Careful comparisons against its official copies showed the masses diverging by tens of micrograms, and because the prototype simply was the kilogram by definition, there was no way to say which side had changed. In 2019 it was redefined in terms of the Planck constant, so any properly equipped lab can now realise a kilogram from physics rather than from an artefact.

What is a Pound?

The pound descends from the Roman libra pondo, "a pound by weight", which is why English took pound from the second word and the abbreviation lb from the first. The version used here is the avoirdupois pound, from an Old French phrase meaning "goods of weight" — the merchants’ system for ordinary bulk trade. A separate troy pound survived for precious metals and was never the same size. The 1959 international yard and pound agreement finally fixed the avoirdupois pound at exactly 0.45359237 kilograms across the English-speaking world, ending a long tail of national variants.

To put both in perspective: a liter of water weighs about a kilogram, while a pound is roughly a loaf of bread.

The converter above updates as you type, and the table lists common values for quick reference. Need the opposite direction? Use the Pounds to Kilograms converter, or browse all Weight & Mass converters.