What Are the Metric Sizes?

Gabriel Mouton first proposed the concept of the metric system for both length and time in 1670; however, it was not until 1790 that the French Academy of Sciences devised the metric system that is standard nearly everywhere but the United States today. The meter is the basis for all measurements in the metric system, with mass, area and volume being derived from this unit of length. Smaller and larger increments are created by multiplying or dividing by multiples of 10.

Length

The meter forms the basis of not only units of length, but of the entire metric system. Originally, it was equal to one ten-millionth of the distance between the North Pole and the equator along the meridian near Dunkirk, France, and Barcelona, Spain. Other sizes, such as the centimeter, are formed by moving the decimal place to the left or right a certain number of spaces. For example, a millimeter is 0.001 meter. This derives from the prefix milli-, meaning thousandth.

Area

Area represents the amount of space taken up by a surface, represented by a meter squared. The formula for determining area depends on the shape. For example, a square with 4-meter sides has an area of 4 m * 4 m = 16 m^2 or 16 square meters. The prefixes for different sizes remain the same. One square meter equals 1.0 x 10^-6 square kilometers.

Volume

Volume is the measure of the amount of space contained in an object, represented by a cubic meter. For example, a cube with sides 4 mm in length would have a volume equal to 4 mm * 4 mm * 4 mm = 64 mm^3. For liquid volume, the standard unit of measure is the liter. This is found by dividing the mass by the density of the liquid.

Mass

Mass is the measure of how much matter an object has. The standard unit of measurement is the gram, which is the mass of one cubic centimeter of water at its temperature of maximum density. Converting between sizes is the same for mass as it is for length, area and volume. Mass differs from weight in that the mass of an object is constant anywhere in the universe, whereas the weight of an object is the measure of the force of gravity acting on that object's mass.