Convert pounds (lbs) to kilograms accurately. Essential for international shipping, fitness tracking, and medical dosing. Real examples and industry standards included.
1 pound equals 0.45359290943563974 kilogram
Formula: kg = lb × 0.453592
The pound to kilogram conversion connects the imperial weight system used in the United States with the metric system used by 95% of the world. This fundamental conversion impacts everything from calculating shipping costs to tracking fitness progress, making it one of the most frequently needed weight conversions globally.
Every day, millions of packages cross borders requiring weight conversion from pounds to kilograms. Airlines charge for baggage by the kilogram internationally but weigh in pounds at US airports. Fitness apps need to work globally, medical dosing requires precise conversion, and international trade depends on accurate weight specifications. A simple conversion error can mean overloaded trucks, rejected shipments, or incorrect medication doses.
Global shipping relies on accurate pound to kilogram conversion. Container weight limits, customs declarations, and freight charges all require precise conversion to avoid penalties and delays.
The fitness industry straddles both systems - US gyms use pounds while most fitness science uses kilograms. Athletes, trainers, and nutritionists constantly convert between systems.
Medicine dosing worldwide uses mg/kg, but US patients know their weight in pounds. Accurate conversion can be literally life-saving for weight-based drug dosing.
| pounds | kilograms |
|---|---|
| 10 lb | 4.535929 kg |
| 50 lb | 22.679645 kg |
| 100 lb | 45.359291 kg |
| 500 lb | 226.796455 kg |
| 1000 lb | 453.592909 kg |
Formula: kg = lb × conversion factor
The pound is a widely used unit for measuring weight. It is commonly used in various applications and industries worldwide.
The kilogram is a widely used unit for measuring weight. It is commonly used in various applications and industries worldwide.
This pound to kilogram converter uses high-precision conversion factors to ensure accurate results for professional and academic use.
Our calculator provides results with up to 10 decimal places for maximum accuracy.
The 45 lb plate is actually a compromise - it's very close to 20 kg (44.09 lbs), which is the international standard. When Olympic lifting became popular, equipment manufacturers made plates that worked for both systems. Similarly, a '35 lb' plate is really 15 kg (33.07 lbs).
Divide pounds by 2.2 for a quick estimate. For more accuracy, divide by 2 and subtract 10%. Example: 180 lbs ÷ 2 = 90, minus 9 (10%) = 81 kg. The actual answer is 81.65 kg, so you're within 1%.
Weight-based dosing accounts for body size differences, ensuring therapeutic effectiveness while minimizing toxicity. A dose safe for a 50 kg person might be ineffective for someone weighing 100 kg, or toxic for someone weighing 25 kg. This is especially critical in pediatrics.
Pound-mass (lbm or just lb) measures mass/weight. Pound-force (lbf) measures force. On Earth's surface, 1 lbm weighs 1 lbf, but they're different units. In engineering, this distinction matters for calculations involving acceleration. Most everyday uses mean pound-mass.
Yes! Overweight baggage fees can be substantial. US airlines typically charge for bags over 50 lbs (22.68 kg), but international carriers use 23 kg (50.71 lbs). That 0.71 lb difference could trigger an overweight fee if you packed exactly 50 lbs thinking you were safe.
Browse our collection of 6 Weight converters. Each converter provides instant, accurate results for professional and academic use.