Square Kilometers to Square Miles Converter

Use this converter to easily convert between Square Kilometers and Square Miles (sq km to sq mi).

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How many Square Kilometers are in a Square Mile?

There are approximately 2.59 square km are in a square mile, since a mile is defined as 5,280 feet and a foot is defined as 0.3048 meters, then a mile is 1.609344 km and a square mile in km is the area of a square with a side of 1.609344 km. The symbol for square miles is "mi2", often written as "sq mi" while the symbol for square kilometer is "km2", occasionally written as "sq km". Note that writing square miles as m2 or "sq m" could easily lead to confusion with square meters.

Difference between Square Kilometers and Square Miles

Both square kilometers and square miles are units of area of similar magnitude and are both used to measure tracts of land. The square kilometer is a part of the metric system established via the International system of units (SI), while the square mile is a part of the Imperial system of units. "Imperial" is referring to the British Empire in which the unit saw most recent widespread usage.

The meter is a fairly more recent invention with the first definition being set in the year 1793 – 1/10,000,000 of the distance between the equator and the North Pole. The meter was redefined last in 1983 as being equal to the distance light travels in 1/299,792,458 seconds in a vacuum. The kilometer is defined relative to the meter and equals exactly 1,000 meters. A square kilometer is then the area of a square with a side of 1 kilometer, or 1,000,000 m2.

Miles as a measurement unit date as far back as the Roman Empire. Over time and in different places there existed different definitions for the mile with some of the more widely known being the English mile, Scot mile, Italian mile. Miles are currently only used in a couple of countries in the world like the United States and the United Kingdom. The mile is currently defined to be exactly 1609.344 meters long. A square mile is the area of a square with a side of one mile.

How to convert Square Kilometers to Square Miles

To convert sq mi to sq km, divide the measurement in square miles by 2.589988110336 to get the area in square kilometers. Using a calculator is most helpful snice this division is not trivial when done by hand, even with small numbers. Our free online square kilometers to square miles converter should be of great help.

Square Kilometers to Square Miles conversion example

Sample task: convert 10 km2 to mi2. Solution:

Formula:
km2 / 2.589988110336 = mi2
Calculation:
10 km2 / 2.59 = 3.861022 mi2
End result:
10 km2 is equal to 3.861022 mi2

Square Kilometers to Square Miles conversion table

sq km to sq mi conversion table
sq km sq mi
1 sq km 0.386102 sq mi
2 sq km 0.772204 sq mi
3 sq km 1.158306 sq mi
4 sq km 1.544409 sq mi
5 sq km 1.930511 sq mi
6 sq km 2.316613 sq mi
7 sq km 2.702715 sq mi
8 sq km 3.088817 sq mi
9 sq km 3.474919 sq mi
10 sq km 3.861022 sq mi
20 sq km 7.722043 sq mi
30 sq km 11.583065 sq mi
40 sq km 15.444086 sq mi
50 sq km 19.305108 sq mi
60 sq km 23.166130 sq mi
70 sq km 27.027151 sq mi
80 sq km 30.888173 sq mi
90 sq km 34.749194 sq mi
100 sq km 38.610216 sq mi
200 sq km 77.220432 sq mi
300 sq km 115.830648 sq mi
400 sq km 154.440863 sq mi
500 sq km 193.051079 sq mi
600 sq km 231.661295 sq mi
700 sq km 270.271511 sq mi
800 sq km 308.881727 sq mi
900 sq km 347.491943 sq mi
1,000 sq km 386.102159 sq mi

References:

[1] NIST Special Publication 330 (2008) - "The International System of Units (SI)", edited by Barry N.Taylor and Ambler Thompson

[2] International Organization for Standardization (1993). ISO Standards Handbook: Quantities and units (3rd edition). Geneva: ISO. ISBN 92-67-10185-4.

Cite this converter & page

If you'd like to cite this online converter resource and information as provided on the page, you can use the following citation:
Georgiev G.Z., "Square Kilometers to Square Miles Converter", [online] Available at: https://www.gigacalculator.com/converters/convert-square-kilometers-to-sq-miles.php URL [Accessed Date: 18 Sep, 2019].