How many pounds are in a kilogram?

2.20462 pounds. Precisely, 1 ÷ 0.45359237. The reverse is exact: a pound is defined as 0.45359237 kilograms.

Is a ton the same as a tonne?

No. A metric tonne is exactly 1,000 kg. A US short ton is 2,000 lb, about 907 kg. A British long ton is 2,240 lb, about 1,016 kg. This converter uses the US short ton.

Weight and Mass Converter

Convert between grams, kilograms, tonnes, ounces, pounds, stone and US tons.

Draft — figures checked, awaiting an editorial read. Not indexed.

Result—

Formula: Result = amount × (factor of source unit ÷ factor of target unit), with every factor expressed in kilograms.

What this calculates

This converts mass between the metric and US customary systems, including stone, which is still the everyday unit for body weight in Britain and Ireland and appears nowhere else. Like length, the key factors are exact by definition: the international pound has been exactly 0.45359237 kilograms since 1959. The ounce is a sixteenth of that, and the stone is fourteen pounds. Everything else follows arithmetically.

How it works

Every unit carries a factor expressing it in kilograms. The amount is multiplied by the source factor to reach kilograms and divided by the target factor to leave them. Two units here deserve a note. The "ton" in this converter is the US short ton of 2,000 pounds, which is about 907 kilograms — not the metric tonne of exactly 1,000 kilograms, and not the imperial long ton of 2,240 pounds still occasionally used in Britain. The three differ by up to 12%, which is a large error to make by accident.

Worked example

Converting 165 pounds to kilograms: 165 × 0.45359237 = 74.84 kilograms. To stone, which is how the same figure would be quoted in the UK: 165 ÷ 14 = 11.79 stone, usually spoken as "11 stone 11". And a 1 kilogram bag of flour is 1 ÷ 0.45359237 = 2.2046 pounds, which is where the familiar "2.2 pounds to the kilo" comes from.

Common mistakes

Mixing up the three different tons is the expensive one, particularly in shipping and materials ordering. Second, confusing mass with weight — strictly these are different quantities, and what a bathroom scale reports is mass even though everyone calls it weight. Third, using fluid ounces and ounces interchangeably: one measures volume and one measures mass, and they are only numerically close for water by coincidence of how the units were defined. Fourth, and easy to miss, the troy ounce used for gold, silver and other precious metals is a different unit again at about 31.1 grams against the ordinary avoirdupois ounce of 28.35 — roughly 10% heavier. This converter uses the avoirdupois ounce throughout, so a precious metal quote will not reconcile against it.

Common questions

How many pounds are in a kilogram?: 2.20462 pounds. Precisely, 1 ÷ 0.45359237. The reverse is exact: a pound is defined as 0.45359237 kilograms.
Is a ton the same as a tonne?: No. A metric tonne is exactly 1,000 kg. A US short ton is 2,000 lb, about 907 kg. A British long ton is 2,240 lb, about 1,016 kg. This converter uses the US short ton.