1 lb to kg — 0.4536 kilograms
1 lb is exactly 0.4536 kilograms. Multiply by 0.453592 to convert any value from lbs to kg.
Lbs to kg
LiveThe formula
Take the number of lbs and multiply it by 0.453592: 1 × 0.453592 = 0.4536 kg. The factor comes from the international definition of the units, so the result is exact rather than an estimate — only the displayed value is rounded.
| Result | 0.4536 kg |
|---|
Where this measurement turns up
- US packaging labels
- postage rates
- dumbbells
Worth knowing
Dividing by 2.2 is the shortcut everyone learns, yet the exact factor is 0.45359237. At 200 pounds the shortcut is off by roughly 200 grams, which matters for medication dosing and for weight classes in competitive sport.
Questions people ask
1 lb is exactly 0.4536 kilograms. The calculation is 1 × 0.453592.
Multiply the value in lbs by 0.453592. To go the other way, divide the kg figure by the same number.
The conversion factor is defined by international standard, so the underlying result is exact. We round the display to a sensible number of decimal places, which is why you may see a slightly shorter figure than a calculator gives.
Need the reasoning, not just the number?
Our guides explain how each measurement is defined, where it is used and which mistakes cost people money.