Square Foot [ft2] to Square Kilometer [km2] Converter

Definition: A square foot (ft²) is a unit of area equal to the area of a square that is 1 foot on each side. It is commonly used in the United States and other countries that use the imperial system.

History/origin: The square foot is derived from the foot, which has ancient origins and was traditionally based on the length of a human foot. Its exact definition has varied throughout history.

Current use: Square feet are widely used for measuring the area of rooms, buildings, land, and other surfaces. It's a standard unit in real estate, construction, and many other fields in the US.

Definition: A square kilometer (km²) is a unit of area equal to a square that is 1 kilometer on each side. It is a multiple of the square meter, the SI unit of area.

History/origin: The square kilometer is derived from the kilometer, which is part of the metric system established in France in the late 18th century. The metric system was designed to be a standardized and coherent system of measurement based on decimal multiples.

Current use: Square kilometers are used to measure large areas, such as the size of cities, countries, lakes, and other geographical features. It's a common unit in geography, cartography, and environmental studies.