Mass / Weight Converter

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Use this weight & mass converter to convert instantly between pounds, ounces, kilograms, grams, stones, tonnes and other metric and imperial weight units. You can find out the difference between mass and weight here. If you wish to convert between kg, stone, pounds, ounces, take a look at the weight converter.

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Whilst every effort has been made in building this mass / weight converter, we are not to be held liable for any special, incidental, indirect or consequential damages or monetary losses of any kind arising out of or in connection with the use of the converter tools and information derived from the web site. This mass / weight converter is here purely as a service to you, please use it at your own risk. Do not use calculations for anything where loss of life, money, property, etc could result from inaccurate conversions.

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Conversion units currently available for the mass and weight converter

Carats (metric) (CM), Centigrams (cg), Decigrams (dg), Dekagrams (dag), Grains (gr), Grams (g), Kilograms (kg), Micrograms (mcg), Milligrams (mg), Newtons (N), Ounces Avoir (oz), Ounces Troy (t oz), PennyWeights (pwt), Pounds Avoir (lb), Pounds Troy, Slugs, Stone (UK) (st), Stone (US), Tonnes (metric ton) (t), Tons (UK long ton), Tons (US short ton),

A gold weight conversion tool is also available. Other individual mass and weight converters available include those for kg to stones & pounds, kg to pounds & ounces and ounces to ounces troy.

Mass / Weight Converter Definitions

Ounce Avoir

An avoirdupois ounce is equal to 28.349523125 grams. The ounce is commonly used as a unit of mass in the United States and around the World.

Ounce Troy

A troy ounce (abbreviation: t oz) is equal to 31.1034768 grams. Today, the troy ounce is used only to express the mass of precious metals such as gold, platinum or silver.

Pound Avoir

The pound (abbreviations: lb or, sometimes in the United States, #) is a unit of mass in a number of different systems, including various systems of units of mass that formed part of English units, Imperial units, and United States customary units. Its size can vary from system to system. The most commonly used pound today is the international avoirdupois pound.

Pound Troy

Troy weight originates from the troy system of mass and dates back to before the time of William the Conqueror. The troy pound is no longer in general use. In Canada, Australia, the UK, and other places the troy pound is no longer a legal unit for trade. In the United Kingdom, the use of the troy pound was abolished on 6 January 1879. The troy pound is still used for measurements of precious metals such as gold, silver, and platinum, and sometimes gems such as opals.

If you're converting between pounds and ounces, see our post on how many ounces are in a pound.