Pounds to Kilograms Converter
Convert any weight from pounds to kilograms using the internationally defined conversion factor: 1 lb = 0.45359237 kg. This converter also displays grams, ounces, and stones for complete reference.
The pound (lb) is the primary unit of weight in the United States customary system, while the kilogram (kg) is the SI base unit of mass used internationally. The international avoirdupois pound is defined as exactly 0.45359237 kilograms. This converter uses that precise definition.
Common Pound to Kilogram Conversions:
| Pounds | Kilograms | Context |
|---|---|---|
| 1 lb | 0.4536 kg | Base conversion |
| 5 lbs | 2.268 kg | Bag of sugar |
| 10 lbs | 4.536 kg | Newborn baby |
| 50 lbs | 22.680 kg | Carry-on limit |
| 100 lbs | 45.359 kg | Light adult |
| 150 lbs | 68.039 kg | Average adult |
| 200 lbs | 90.718 kg | Above-average adult |
| 250 lbs | 113.398 kg | Heavy adult |
Tip for Quick Estimation: Divide the pound value by 2, then subtract 10% of the result. For example, 180 lbs: half is 90, minus 10% (9) = 81 kg (actual: 81.65 kg). Alternatively, just multiply by 0.45 for a close approximation.