Unit converters

Mass converter

Convert mass between commonly used units with the measurement system clearly identified.

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Behind the numbers

How this calculation works

Both units are mapped to a shared base unit using fixed conversion factors. US and imperial volume units are distinct; area factors are squared length factors.

THE FORMULAConverted value = value × source factor ÷ destination factor

A worked example

1 kilograms = approximately 2.204622621849 pounds.

Good to know

Results use fixed factors and rounded decimal display. Region-specific land measures and fluid/dry units not listed here are not inferred.

A little curiosity

Kilograms measure mass, not a force in newtons

Mass and weight are related but different. This converter changes mass units such as kilograms, grams and pounds; it does not calculate gravitational force. A force calculation also needs the relevant acceleration.

A kilogram contains 1,000 grams, so converting a small mass to grams can make its number easier to read without changing the underlying quantity.

An ounce needs a definition

The ounce here is the ordinary avoirdupois mass ounce, one sixteenth of an avoirdupois pound. It is not a fluid ounce, which measures volume, and it is not the troy ounce used in some precious-metal quotations.

The tonne is a metric tonne of 1,000 kg, not a US short ton or an imperial long ton. Do not apply this list to an unqualified “ton” in a source without checking the intended system.

A few questions, answered

Does this convert fluid ounces?

No. Use the volume converter for supported fluid-volume units.

Does changing temperature alter the mass conversion factor?

No. These fixed mass-unit factors do not depend on the sample’s temperature.

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