Weight & Mass Converter
Convert everyday weights and scientific mass measurements between metric SI units, imperial stones and pounds, and US customary tons with exact decimal precision.
1 kg = 2.204623 lb
Common Conversions
How Weight and Mass Conversions Work
All conversions are anchored to the International System of Units (SI) base unit of the kilogram (kg). Every imperial and customary unit is defined internationally by exact treaty relative to the kilogram. For instance, under the 1959 International Yard and Pound Agreement, the avoirdupois pound is defined as exactly 0.45359237 kg.
Mass vs. Weight: Scientific Distinction
In physics, mass is an intrinsic property measuring the quantity of matter in an object (measured in kilograms or grams), whereas weight is the force exerted on that mass by gravity (measured in Newtons).
In commerce, cooking, medicine, and everyday life, "weight" is universally understood to mean mass measured under standard Earth gravity (9.80665 m/s ²). EverydayNumbers uses the user-friendly title "Weight Converter" to match everyday search intent while adhering strictly to rigorous scientific mass ratios.
Official Mass Standards & Ratios
| Unit | Symbol | System | Exact Definition in Kilograms |
|---|---|---|---|
| Gram | g | Metric SI | 0.001 kg |
| Milligram | mg | Metric SI | 0.000001 kg |
| Metric Tonne | t | Metric SI | 1,000 kg |
| Pound (Avoirdupois) | lb | Imperial / US | 0.45359237 kg |
| Ounce (Avoirdupois) | oz | Imperial / US | 0.028349523125 kg (1/16 lb) |
| Stone | st | British Imperial | 6.35029318 kg (14 lb) |
| US Short Ton | ton | US Customary | 907.18474 kg (2,000 lb) |
Common Worked Examples
Example 1: Converting 1 Kilogram to Pounds
1 ÷ 0.45359237 = 2.204623 pounds.
Example 2: Converting 154 Pounds to Stones and Kilograms
154 lb ÷ 14 lb/st = 11.0 stones.
154 × 0.45359237 = 69.8532 kg.