Square kilometre

decimal multiple of the SI unit of surface area
(Redirected from Square kilometer)

A square kilometer (British English spelling square kilometre, in short km²) is a unit of measurement of area. It is based on the SI unit meter.

100 hectares make one square kilometer.

Equal areas


A square that has a side length of 1 kilometer (1000 meters) has an area of one square kilometer.

1,000 m × 1,000 m = 1 km × 1 km = 1,000,000 m² = 1 km²[1]

There are 100 hectares in one square kilometer.[2][1] One square kilometer is just less than 0.39 square miles.[1]

Square kilometer is often used to say how much surface something occupies on Earth. It can, for example, be used to describe the area of a city or country. These usually take more than 1 km² on Earth.

The number of people living in a square kilometer is known as population density.


  1. 1.0 1.1 1.2 "Common Weights and Measures". The Columbia Electronic Encyclopedia (6th ed.). Columbia University Press. January 24, 2017. Archived from the original on April 21, 2023. Retrieved April 21, 2023.
  2. "15 Questions About Units of Measurement Answered". Encyclopaedia Britannica. August 26, 2021. Retrieved April 21, 2023. There are 100 hectares in 1 square kilometer […]