Pounds (lb) to Kilograms (kg) Conversion
Pounds
The pound (avoirdupois) is a unit of mass equal to exactly 0.45359237 kilograms, standardised in 1959. It is the primary unit of mass in the US customary and British imperial systems, used for body weight, food packaging, and commercial transactions. The pound is subdivided into 16 ounces. In US engineering, the distinction between pound-mass (lbm) and pound-force (lbf) is a frequent source of calculation errors.
Kilograms
The kilogram is the SI base unit of mass. From 1889 to 2019, it was defined by the International Prototype of the Kilogram — a physical cylinder of platinum-iridium alloy stored near Paris. In 2019, the kilogram was redefined in terms of Planck's constant (h = 6.62607015 × 10⁻³⁴ J·s), making it the first base unit defined entirely by a fundamental constant of nature. This eliminated the risk of the kilogram gradually changing mass due to contamination of the physical prototype.
| Pounds (lb) | Kilograms (kg) |
|---|---|
| 0.1 lb | 0.045359237 kg |
| 1 lb | 0.45359237 kg |
| 2 lb | 0.90718474 kg |
| 3 lb | 1.36077711 kg |
| 5 lb | 2.26796185 kg |
| 10 lb | 4.5359237 kg |
| 20 lb | 9.0718474 kg |
| 30 lb | 13.6077711 kg |
| 50 lb | 22.6796185 kg |
| 100 lb | 45.359237 kg |
| 1000 lb | 453.59237 kg |