Weight & Mass Converter
Interactive StudioConvert between metric, imperial, and specialty mass units: micrograms, milligrams, carats, grams, kilograms, tonnes, ounces, pounds, stones, US short tons, and UK long tons. Instant feedback with zero server storage.
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About Weight & Mass Converter
Mass and weight conversions bridge metric decimal standards with historical avoirdupois and gemstone measures.
All imperial conversions utilize standard exact international definitions: 1 pound (lb) = exactly 453.59237 grams, 1 ounce (oz) = 28.349523125 grams, 1 stone = 14 pounds (approx 6.3503 kg), and 1 metric carat = 0.2 grams.
How to use Weight & Mass Converter
- Type the value you want to convert.
- Choose the unit you are converting from and the unit you want, such as kilograms, grams, pounds, ounces, stone or carats.
- Read the converted value instantly. Swap the units to convert the other way.
- Copy the result, or check other units listed in the results grid.
Worked examples
Input: 150 lb to kg
Result: About 68.04 kg.
Input: 1 stone to kg
Result: About 6.35 kg (14 pounds).
Input: 5 carats to grams
Result: 1 gram.
Background
The pound is defined exactly as 0.45359237 kg. An ounce is 1/16 of a pound (28.349523125 g), a stone is 14 pounds and a metric carat is 0.2 g. Conversions go through grams.
Strictly, kilograms measure mass and pounds-force measure weight, but in everyday use the units are treated as interchangeable on Earth.
Common mistakes
- Confusing a troy ounce, used for precious metals (31.1035 g), with an avoirdupois ounce (28.35 g).
- Forgetting that a stone is 14 pounds, not 10.
- Mixing carat (gem weight) with karat (gold purity).
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