Topic summary
Square kilometre
The square kilometre (square kilometer in American spelling; symbol: km) is a multiple of the square metre, the SIunit of area or surface area. In the SI unit of area (m), 1 km is equal to 1M(m).
1 km is equal to:
- 1,000,000 square metres (m)
- 100 hectares (ha)
It is also approximately equal to:
- 0.3861 square miles
- 247.1 acres
Conversely:
- 1 m = 0.000001 (10) km
- 1 hectare = 0.01 (10) km
- 1 square mile = 2.5899 km
- 1 acre = about 0.004047 km
The symbol "km" means (km), square kilometre and not k(m), kilo–square metre. For example, 3 km is equal to 3×(1,000m) = 3,000,000 m, not 3,000 m.