Square Foot to Square Kilometer Converter

A square foot (ft²) is a unit of area equal to the area of a square with sides of one foot each. It equals 144 square inches or approximately 0.093 square meters, making it one of the most commonly used area units in imperial systems.

The square foot developed from the English foot, which has ancient origins based on human body measurements. As the foot became standardized (defined as exactly 0.3048 meters in 1959), the square foot became the primary unit for measuring building areas, rooms, and properties in countries using imperial units.

Square feet are extensively used in the United States for measuring floor areas, room sizes, apartments, houses, and commercial spaces. They're standard in real estate listings, construction specifications, HVAC calculations, and building codes. Most American property measurements use square feet.

A square kilometer (km²) is a unit of area equal to the area of a square with sides of one kilometer each. It equals 1,000,000 square meters or 100 hectares, making it suitable for measuring large geographical areas.

The square kilometer emerged naturally from the metric system established during the French Revolution in 1795. As the kilometer became standardized for distance measurement, its square became the logical unit for large area measurements, particularly useful for mapping territories and countries.

Square kilometers are universally used for measuring countries, states, cities, large properties, national parks, and geographical features. They're standard in atlases, geographic surveys, urban planning, and environmental studies. Most countries report their total area in square kilometers.