Square kilometre (U.S. spelling: square kilometer), symbol km², is a decimal multiple of SI unit of surface area square metre, one of the SI derived units. 1 km² is equal to: Motto: (Out Of Many, One) (traditional) In God We Trust (1956 to date) Anthem: The Star-Spangled Banner Capital Washington D.C. Largest city New York City None at federal level (English de facto) Government Federal constitutional republic  - President George Walker Bush (R)  - Vice President Dick Cheney (R) Independence from... Look up si, Si, SI in Wiktionary, the free dictionary. ... The former Weights and Measures office in Middlesex, England. ... Area is the measure of how much exposed area any two dimensional object has. ... A square metre (US spelling: square meter) is by definition the area enclosed by a square with sides each 1 metre long. ... SI derived units are part of the SI system of measurement units and are derived from the seven SI base units. ...

• the area of a square measuring 1 kilometre on each side
• 1, 000 m²
• 100 hectares
• 0.386 102 square miles (statute)
• 247.105 381 acres

Conversely: For other uses, see Square. ... km redirects here. ... A square metre (US spelling: square meter) is by definition the area enclosed by a square with sides each 1 metre long. ... A hectare (symbol ha) is a unit of area, equal to 10 000 square metres, commonly used for measuring land area. ... A square mile is an English unit of area equal to that of a square with sides each 1 statute mile (≈1,609 m) in length. ... An acre is the name of a unit of area in a number of different systems, including Imperial units and United States customary units. ...

• 1 m² = 0.000 001 km²
• 1 hectare = 0.01 km²
• 1 square mile = 2.589 988 km²
• 1 acre = 0.004 047 km²

Note: "km²" means square kilometre and not kilo–square metre. For example, 3 km² is equal to 3 * (1,000 m)² = 3,000,000 m², not 3,000 m². A square mile is an English unit of area equal to that of a square with sides each 1 statute mile (≈1,609 m) in length. ...

Comparative order

The 10⁶ m² orders of magnitude page gives comparisons with geographic areas. To aid in the comparison of sizes of different geographic regions, areas between 1 km² (100 hectares) and 10 km² (1000 hectares) are listed below. ... An order of magnitude is the class of scale or magnitude of any amount, where each class contains values of a fixed ratio to the class preceding it. ...

A hectare (10⁴ m²) is less than a square kilometre which is less than a square megametre (10¹² m²). A hectare (symbol ha) is a unit of area, equal to 10 000 square metres, commonly used for measuring land area. ... Square megametre (symbol Mm2) is an SI unit of surface area. ...

See also

• Conversion of units.
• SI prefix for the precise meaning of the prefix "k"
• Square Kilometre Array, a proposed radio telescope which is intended to have a collecting area of approximately one square kilometre.