Kilograms to Pounds
Pounds to Kilograms
The conversion
One kilogram is exactly 2.20462262 pounds. The relationship is fixed by definition: a pound is defined as exactly 0.45359237 kilograms.
Quick mental conversion
Double the kilograms and add 10%. For 70 kg: double to 140, add 14, giving 154 lb. The exact figure is 154.3 — close enough for most purposes.
Going the other way, halve the pounds and subtract 10%. For 180 lb: half is 90, less 9 gives 81 kg. Exact is 81.6.
Common values
| kg | lb | kg | lb |
|---|---|---|---|
| 5 | 11.0 | 70 | 154.3 |
| 10 | 22.0 | 75 | 165.3 |
| 25 | 55.1 | 80 | 176.4 |
| 50 | 110.2 | 90 | 198.4 |
| 60 | 132.3 | 100 | 220.5 |
Stones, and why they confuse people
Body weight in the UK and Ireland is commonly given in stones and pounds. One stone is 14 pounds.
80 kg is 176.4 lb. Divided by 14 that is 12 stone with 8.4 pounds left over — written 12 st 8 lb.
The remainder is pounds, not a decimal of a stone. "12.6 stone" and "12 stone 6" are different weights: 12.6 stone is 12 st 8.4 lb.
Mass and weight
Strictly, kilograms measure mass and pounds-force measure weight, which is mass under gravity. In everyday use on Earth the distinction doesn't matter and the two are used interchangeably. It only becomes relevant in physics problems or anywhere gravity differs.
Note also that the US and UK once used slightly different pound definitions. They were unified in 1959, so any modern conversion uses the same figure on both sides of the Atlantic.