How the weight converter works
The converter turns your value into kilograms and then into the target unit. The avoirdupois pound used in the US and UK is defined as exactly 0.45359237 kg.
1 oz = 28.349523125 g
1 stone = 14 lb · 1 US ton = 2,000 lb · 1 tonne = 1,000 kg
Strictly speaking, kilograms and pounds measure mass, while weight is the force of gravity on that mass; in everyday use they are treated the same. Troy ounces, used for precious metals, are heavier (31.103 g) than the ounces used for food, and the UK long ton is 2,240 lb.
Worked example
A person weighing 150 lb weighs 150 × 0.45359237 = 68.04 kg, or 10 stone 10 lb. A 12 oz steak is 340.2 g, and a 2,000 lb US ton is 907.18 kg.
Frequently asked questions
How many pounds are in a kilogram?
About 2.20462.
How many grams are in an ounce?
28.3495 grams.
How many pounds is a stone?
14 pounds.
What is the difference between a ton and a tonne?
A US ton is 2,000 lb (907 kg); a metric tonne is 1,000 kg (2,204.6 lb).
Updated October 2026. Results are estimates for education, not financial or medical advice. All math runs in your browser; nothing you type is sent anywhere.