Square Miles to Square Kilometers
Convert square miles to square kilometers and back, instantly.
Compare large geographic areas
Square miles are common for counties, cities, parks, and regional land areas in the United States, while square kilometers are the international metric counterpart. Since area extends in two dimensions, the linear mile-to-kilometer factor must be squared, producing the larger factor used by this converter.
The default 2 square miles converts to 5.17998 square kilometers. In reverse, 1 square kilometer converts to 0.386102 square miles. The reference table is useful for broad comparisons, but every input must already represent area rather than a single route or boundary length.
Private area translation without mapping
The calculation runs entirely in your browser and does not send a place name, coordinate, or area to a mapping provider. It changes units only. Determining the area of an irregular region still requires authoritative boundary data and an appropriate geographic or surveying method.
Frequently Asked Questions
How many square kilometers are in one square mile?
One square mile equals approximately 2.58999 square kilometers.
Why is the factor not the same as miles to kilometers?
Area has two dimensions, so the linear mile-to-kilometer factor is squared.
Can this compare city or park areas?
Yes. It converts any stated area in square miles or square kilometers, though it does not calculate boundaries from a map.
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