Square millimeters (mm²) to Square kilometers (km²) Conversion

Square millimeters

The square millimetre is a unit of area equal to one millionth of a square metre (10⁻⁶ m²). In engineering, cross-sectional areas of wires and cables are standardised in square millimetres — electrical cable ratings specify conductor cross-sections in mm² (e.g., 1.5 mm², 2.5 mm², 4 mm²). In materials testing, stress is calculated as force per unit area in megapascals, where the area is expressed in square millimetres.

Square kilometers

The square kilometre is a unit of area equal to one million square metres (10⁶ m²) and is the standard unit for expressing the surface areas of countries, cities, lakes, forests, and other large geographic features. Russia, the world's largest country, covers approximately 17.1 million km². The surface area of Earth is approximately 510.1 million km², of which about 70.8% is ocean.

Convert Square millimeters (mm²) to other units of Area