How Weight Conversion Works
All common weight units are defined against the kilogram. Since 1959 the avoirdupois pound has been exactly 0.45359237 kg, which makes every metric-imperial weight conversion exact by definition — the decimals you see are precision, not approximation.
Convert 176 lb to kilograms: 176 × 0.45359237 = 79.83 kg. And in stone: 176 ÷ 14 = 12 st 8 lb.
Common Weight Conversions
| From | To | Multiply by |
|---|---|---|
| kilograms | pounds | 2.20462 |
| pounds | kilograms | 0.453592 (exact) |
| ounces | grams | 28.3495 (exact) |
| stone | kilograms | 6.35029 (exact) |
| metric tons | pounds | 2,204.62 |
Frequently Asked Questions
How many pounds are in a kilogram?
About 2.2046 lb. The pound is defined as exactly 0.45359237 kg, so 1 kg = 1 ÷ 0.45359237 ≈ 2.20462 lb. The quick mental rule “double it and add 10%” gets you very close.
How many grams are in an ounce?
About 28.35 g (exactly 28.349523125 g). Kitchen recipes often round to 28 or 30 g.
What is a stone?
A British unit equal to 14 pounds (6.35 kg), still commonly used in the UK and Ireland for body weight — someone weighing “11 stone 4” weighs 158 lb or about 71.7 kg.
Is weight the same as mass?
Colloquially yes, technically no: mass (kg) measures how much matter there is, weight is the force gravity exerts on it. On the Moon your mass is unchanged but your weight is a sixth. For everyday conversion purposes on Earth, the distinction doesn’t affect the numbers.
Cite This Calculator
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The CalculatorsGuide Editorial Team. (2026). Weight Converter. CalculatorsGuide. Retrieved from https://www.calculatorsguide.com/conversions/weight-converter/