# Units of area The units of area belong to the most used units in the world. Therefore this group couldn’t be left out of this unit conversion series. This article  reviews the units of area in the UK imperial, US customary and metric system. But before we proceed to area conversions to look at the definition of area we must. ## What is the dimension of area?

The area of an object specifies the two-dimensional space it covers. For instance, rectangular areas are calculated by multiplying the length and width of the object. For spherical, circular and other objects different formula’s apply.

This two dimensional relationship between area and length affects the conversion factors for two dimensional area. The one dimensional length was discussed in the units of length article. Squaring (multiplying with itself) these conversion factors gives the conversion for units of area.

## Imperial units of area conversion

The Imperial and US customary system uses the same units of measure for area. Table 1 displays the area conversion factors for these systems.

From length conversions we know that 1 foot consists of 12 inch. Therefore one square foot must consist of 12^2 = 144 square inch.

We also can define the square yard as the equivalent of 3^2 = 9 square feet.

Furthermore one square rod is built from 5.5^2 or about 30 square yard.

Finally one square mile consists of 320^2 = 102 400 square rod.

## Area conversions from surveyors length

For surveyors units of area only the acre and square feet ares still used in the United States and United Kingdom. The square feet was already discussed in the previous section and is the equivalent of 0.0929 square meter. The acre is calculated by multiplying a square feet with a factor of 43 560. The conversion factors for surveyors area are supplied in table 2.

## Metric area units of area conversion

Finally, the area unit conversion for the metric system proceeds in similar fashion. From one dimensional length we already knew that these convert in steps of 10. Therefore area will convert in steps of 10^2 = 100. Some of the metric units of area are displayed in table 3. Although only square meter and hectare (square hectometer) are the commonly used.