Convert Are (a) to Square Kilometer (km²) instantly.
About these units
Are (a)
An are is a metric land unit equal to 100 m², originally invented during the development of the metric system but now largely overshadowed by the hectare (100 ares). Although rarely used independently in modern measurement, the are survives in real estate transactions in parts of Europe, where small land parcels—such as garden plots or rural homesteads—may be expressed in ares. It remains important historically, as it served as a transitional unit bridging the earliest metric innovations with modern large-scale land measurement practices.
Square Kilometer (km²)
A square kilometer equals one million square meters and is the standard unit for expressing large land areas, especially in geography, ecology, national planning, and environmental science. Countries, cities, national parks, forests, wetlands, and even ocean surface regions are frequently described in km². Because it provides a manageable scale for features too large for hectares or acres, it is widely used in atlases, scientific papers, and government reports. The square kilometer also plays a major role in ecology, where species ranges, habitat fragmentation, and conservation zones are measured using this unit. In geopolitics, km² help define national borders and territorial claims, making it a powerful instrument of scientific and political discourse.