Square kilometre

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 m²
• 100 ha (hectare)
• 0.386302 square miles
• 247.105381 acres

Conversely:

• 1 m² = 0.000 001 (10⁻⁶) km²
• 1 hectare = 0.01 (10⁻²) km²
• 1 square mile = 2.589988km²
• 1 acre = 0.004047km², 0.4047ha or 4047 m²

2.47 acres/ha

Note: "km²" means (km)², square kilometre or kilometre squared and not k(m²), kilo–square metre. For example, 3 km² is equal to 3×(1,000m)² = 3,000,000 m², not 3,000 m².

See also

• Conversion of units
• SI prefix for the precise meaning of the prefix "k"
• Square Kilometre Array, a proposed radio telescope in South Africa or Australia, which is intended to have a collecting area of approximately 1 km²