square kilometer

area whose length and width are both one kilometer, area of one thousand dunams

Square kilometre (U.S. spelling: square kilometer), symbol km², is a decimal multiple of the SI unit of surface area, the square metre, one of the SI derived units. 1 km² is equal to: 1,000,000 m²100 ha (hectare)Conversely:1 m² = 0.000 001 (10-6) km²1 hectare = 0.01 (10-2) km²1 square mile = 2.589 988 km²1 acre = 0.004 047 km², 40.47 ha or 4047 m²Note: "km²" means (km)², square kilometre or kilometre squared, and not k(m²), kilo–square metre. For example, 3 km² is equal to 3 * (1,000 m)² = 3,000,000 m², not 3,000 m².
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M^2 redirects here. For other uses, see M². The square metre (also spelled meter, see spelling differences) is the SI derived unit of area, with symbol m². It is defined as the area of a square whose sides measure exactly one metre. The square metre is derived from the SI base unit of the metre, which in turn is defined as the length of the path travelled by light in absolute vacuum during a time interval of of a second.
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