Weight Converter
Convert mass and weight measurements between metric and imperial standards. Provides exact conversions between kilograms, pounds, ounces, grams, stones, and tonnes.
Weight value to convert
Starting unit of mass
Target converted unit
Resulting mass in target unit
How to Use This Calculator
- Enter the weight or mass value.
- Select the starting unit (kg, lb, g, oz, st, etc.).
- Select the target destination unit.
- Review the converted weight and SI kilogram baseline.
Formula & Calculation Methodology
Mass conversions route through the international kilogram (kg). By treaty, 1 avoirdupois pound equals exactly 0.45359237 kilograms.
Worked Example
Converting 70 kg to pounds
Converting 16 ounces to pounds
Frequently Asked Questions
What is the exact conversion from pounds to kilograms?↓
By international agreement (1959), 1 pound (lb) is legally defined as exactly 0.45359237 kilograms.
What is a stone (st)?↓
A stone is a traditional British imperial unit of mass equal to exactly 14 pounds (approx. 6.35029 kg), widely used in the UK and Ireland for body weight.
What is the difference between mass and weight?↓
Mass is the fundamental quantity of matter in an object (measured in kg or lb-mass) and remains constant everywhere. Weight is the gravitational force exerted on that mass.
What is a metric tonne?↓
A metric tonne (t) equals exactly 1,000 kilograms (approximately 2,204.62 pounds).
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Source Citation & Disclaimer
Informational tool only; not licensed tax, legal, or financial advice.