Convert pounds to kilograms instantly. Enter any pound value and get the exact kilogram equivalent, plus the formula and a full reference table.
The conversion factor is derived from SI base values:
The avoirdupois pound is defined as exactly 0.45359237 kg by international agreement.
| Pounds (lb) | Kilograms (kg) |
|---|---|
| 1 lb | 0.4536 kg |
| 5 lb | 2.268 kg |
| 10 lb | 4.536 kg |
| 25 lb | 11.34 kg |
| 50 lb | 22.68 kg |
| 100 lb | 45.36 kg |
| 130 lb | 58.97 kg |
| 150 lb | 68.04 kg |
| 175 lb | 79.38 kg |
| 200 lb | 90.72 kg |
1 lb equals 0.453592 kg. The exact definition is 0.45359237 kg, set by international agreement in 1959 as part of the International Yard and Pound Agreement.
100 lb equals 45.36 kg. Calculation: 100 × 0.453592 = 45.3592 kg, commonly rounded to 45.36 kg.
150 lbs equals 68.04 kg. Calculation: 150 × 0.453592 = 68.039 kg, rounded to 68.04 kg.
The kilogram is bigger. 1 kg equals approximately 2.205 lbs, so it takes more than two pounds to equal one kilogram.
The pound (lb) abbreviation comes from the Latin "libra pondo" meaning "a pound by weight." The Roman libra was a unit of weight equaling about 329 grams - much lighter than today's avoirdupois pound.