To convert between different metric weight units select the unit from the unit drop down and enter the amount in the amount box. Alternatively to select other conversions select the type of weight from the top drop down boxes.

Metric Weight Units

The kilogram is the base unit of mass of the SI metric system of units. In common usage mass and weight are considered equivalent at earth normal gravity thus weights given in the metric system are given in kilograms and units defined by the kilogram.

The kilogram is the only metric base unit with a prefix (kilo) as part of its name and it is also the only base unit that is still defined by an artifact, the international prototype kilogram (IPK).

There are many defined metric weight units, which use the standard metric prefix, kilo, centi, milli etc, although only a few are in common usage kilogram, gram, milligram and microgram.

The Metric Ton (Tonne)

The metric ton (also known as the tonne) is a metric unit of weight equal to 1,000kg (1 megagram, a term that is almost never used). It is a non SI unit that is in common usage given that it is equal to 2,204.6 lbs which is close to the UK imperial ton (2,240lb) and the US customary units ton (2,000lb).

The Metric Carat

Defined in 1907 this unit of 200 milligrams is used for measuring the weight of gem stones and is one of the very few metric units to have been adopted in the United States and also in Britain prior to formal metrication in that country.

Table of Units

There are many other prefixes that are used such as nanogram, picogram and teragram that are used in science for extremely small and extremely large masses.