Square Mile [mi2] to Square Kilometer [km2] Converter

Quick Reference

1 Square Mile (mi2) = 2.589990617 Square Kilometer (km2)

1 Square Kilometer (km2) = 0.3861017849 Square Mile (mi2)

How to Convert Square Mile to Square Kilometer

1 mi2 = 2.5899906167838798 km2
1 km2 = 0.3861017848943985 mi2

To convert Square Mile to Square Kilometer, multiply the value by 2.589990617. To convert Square Kilometer back to Square Mile, divide by 2.589990617.

Example: convert 10 mi2 to km2:
10 mi2 = 10 x 2.5899906167838798 = 25.899906167838797 km2

↔ Convert Square Kilometer to Square Mile

Square Mile

Definition: A square mile (mi²) is a unit of area equal to the area of a square that is 1 mile on each side. It is commonly used in the United States and other countries that use the imperial system.

History/origin: The square mile is derived from the mile, which has ancient origins and was traditionally based on the distance a Roman legion could march in a certain amount of time.

Current use: Square miles are used to measure very large areas, such as the size of cities, counties, and regions. It's a common unit in geography, cartography, and environmental studies in the US.

Square Kilometer

Definition: A square kilometer (km²) is a unit of area equal to a square that is 1 kilometer on each side. It is a multiple of the square meter, the SI unit of area.

History/origin: The square kilometer is derived from the kilometer, which is part of the metric system established in France in the late 18th century. The metric system was designed to be a standardized and coherent system of measurement based on decimal multiples.

Current use: Square kilometers are used to measure large areas, such as the size of cities, countries, lakes, and other geographical features. It's a common unit in geography, cartography, and environmental studies.

Square Mile to Square Kilometer Conversion Table

Square Mile [mi2]	Square Kilometer [km2]
1 mi2	2.5899906167838798 km2
2 mi2	5.1799812335677595 km2
5 mi2	12.949953083919398 km2
10 mi2	25.899906167838797 km2
20 mi2	51.79981233567759 km2
50 mi2	129.499530839194 km2
100 mi2	258.999061678388 km2
200 mi2	517.998123356776 km2
500 mi2	1294.99530839194 km2
1000 mi2	2589.99061678388 km2

Common pairs of Area

Square Millimeter

Square Millimeter to Centimeter Square Millimeter to Square Meter Square Millimeter to Hectare Square Millimeter to Square Kilometer Square Millimeter to Square Inch

Centimeter

Centimeter to Square Millimeter Centimeter to Square Meter Centimeter to Hectare Centimeter to Square Kilometer Centimeter to Square Inch

Square Meter

Square Meter to Square Millimeter Square Meter to Centimeter Square Meter to Hectare Square Meter to Square Kilometer Square Meter to Square Inch

Hectare

Hectare to Square Millimeter Hectare to Centimeter Hectare to Square Meter Hectare to Square Kilometer Hectare to Square Inch

Square Kilometer

Square Kilometer to Square Millimeter Square Kilometer to Centimeter Square Kilometer to Square Meter Square Kilometer to Hectare Square Kilometer to Square Inch

Square Inch

Square Inch to Square Millimeter Square Inch to Centimeter Square Inch to Square Meter Square Inch to Hectare Square Inch to Square Kilometer

Square Yard

Square Yard to Square Millimeter Square Yard to Centimeter Square Yard to Square Meter Square Yard to Hectare Square Yard to Square Kilometer

Square Foot

Square Foot to Square Millimeter Square Foot to Centimeter Square Foot to Square Meter Square Foot to Hectare Square Foot to Square Kilometer

Acre

Acre to Square Millimeter Acre to Centimeter Acre to Square Meter Acre to Hectare Acre to Square Kilometer

Square Mile

Square Mile to Square Millimeter Square Mile to Centimeter Square Mile to Square Meter Square Mile to Hectare Square Mile to Square Kilometer

Square Mile [mi2] to Square Kilometer [km2] Converter

To convert Square Mile to Square Kilometer, enter your value in the mi2 field above and the result in km2 will appear instantly. You can also use the conversion factor shown in the table on this page to calculate manually. The formula is always the same: multiply your mi2 value by the fixed conversion ratio to get the equivalent in km2.

Our Square Mile to Square Kilometer converter uses standardized conversion factors defined by international scientific and metrological organizations. All calculations are performed with full floating-point precision. You can also choose how many decimal places to display in the result, so you get exactly the level of detail you need.

Yes, absolutely. Simply swap the source and destination units in the converter — select km2 as your input unit and mi2 as your output unit. The same precision and standardized conversion factor applies in both directions.

Converting between Square Mile and Square Kilometer comes up regularly in engineering, scientific research, construction, and everyday tasks that involve measurements from different unit systems. Our converter eliminates the risk of manual calculation errors and saves time whenever you need to switch between these two units.

Yes, the Square Mile to Square Kilometer converter is completely free. No account or registration is required, and there are no usage limits. It works on any device — smartphones, tablets, and desktop computers — directly in your browser.

Square Mile and Square Kilometer are both units used to measure the same physical quantity, but they belong to different measurement systems or represent different scales. The mathematical relationship between them is fixed and constant, which is what makes accurate conversion possible. Scroll up to see the exact conversion factor, formula, and a reference table for common values.

Square Mile [mi2] to Square Kilometer [km2] Converter

Quick Reference

1 Square Mile (mi2) = 2.589990617 Square Kilometer (km2)

1 Square Kilometer (km2) = 0.3861017849 Square Mile (mi2)

How to Convert Square Mile to Square Kilometer

1 mi2 = 2.5899906167838798 km2
1 km2 = 0.3861017848943985 mi2

To convert Square Mile to Square Kilometer, multiply the value by 2.589990617. To convert Square Kilometer back to Square Mile, divide by 2.589990617.

Example: convert 10 mi2 to km2:
10 mi2 = 10 x 2.5899906167838798 = 25.899906167838797 km2

↔ Convert Square Kilometer to Square Mile

Square Mile

History/origin: The square mile is derived from the mile, which has ancient origins and was traditionally based on the distance a Roman legion could march in a certain amount of time.

Current use: Square miles are used to measure very large areas, such as the size of cities, counties, and regions. It's a common unit in geography, cartography, and environmental studies in the US.

Square Kilometer

Definition: A square kilometer (km²) is a unit of area equal to a square that is 1 kilometer on each side. It is a multiple of the square meter, the SI unit of area.

Square Mile to Square Kilometer Conversion Table

Square Mile [mi2]	Square Kilometer [km2]
1 mi2	2.5899906167838798 km2
2 mi2	5.1799812335677595 km2
5 mi2	12.949953083919398 km2
10 mi2	25.899906167838797 km2
20 mi2	51.79981233567759 km2
50 mi2	129.499530839194 km2
100 mi2	258.999061678388 km2
200 mi2	517.998123356776 km2
500 mi2	1294.99530839194 km2
1000 mi2	2589.99061678388 km2