Square Kilometer to Square Mile Conversion Calculator: Free Online Tool

Convert square kilometers to square miles with our free online area converter.

From:

km²

Square Kilometer

To:

mi²

Square Mile

How to Use the Calculator:

Enter the value you want to convert in the 'From' field (Square Kilometer).
The converted value in Square Mile will appear automatically in the 'To' field.
Use the dropdown menus to select different units within the Area category.
Click the swap button (⇌) to reverse the conversion direction.

How to Convert Square Kilometer to Square Mile

Converting Square Kilometer to Square Mile involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Square Kilometer = 0.386102 square miles

Example Calculation:

Convert 10 square kilometers: 10 × 0.386102 = 3.861022 square miles

Note: Conversion factors can sometimes be rounded for display purposes. For precise calculations, always use the full factor or rely on the calculator above.

What is a Square Kilometer and a Square Mile?

The square kilometer (symbol: km²) is a decimal multiple of the SI unit of area, the square meter. It represents the area of a square with sides that are each one kilometer long (1 km² = 1,000,000 m²).

The square mile (symbol: mi², sq mi) is an imperial and US customary unit of area. It represents the area of a square with sides that are each one statute mile long.

Note: The Square Kilometer is part of the metric (SI) system, primarily used globally in science and trade. The Square Mile belongs to the imperial/US customary system.

History of the Square Kilometer and Square Mile

As a multiple of the square meter, the square kilometer came into use alongside the metric system for measuring large areas like land masses, cities, and countries. Its adoption followed the establishment of the kilometer as a standard unit of distance.

Derived from the mile, a unit of distance with Roman origins, the square mile became a standard unit for measuring large land areas in the imperial system, particularly within the British Empire and the United States. It's often used for geographic and administrative divisions.

Common Uses for square kilometers and square miles

Explore the typical applications for both Square Kilometer (metric) and Square Mile (imperial/US) to understand their common contexts.

Common Uses for square kilometers

Geography & Cartography: Standard unit for measuring the land area of cities, regions, countries, and continents.
Demographics: Used to calculate population density (people per km²).
Environmental Science: Measuring the extent of forests, deserts, lakes, or areas affected by environmental changes (e.g., deforestation, wildfires).
Urban Planning: Assessing land use and zoning areas within large municipalities.

Common Uses for square miles

Geography & Cartography (US/UK): Used for measuring large land areas such as counties, national parks, large estates, or city limits in countries using the imperial/US customary system.
Demographics (US/UK): Calculating population density (people per sq mi) in relevant regions.
Surveying: Used in land surveying for large tracts of land.
Historical Records: Appears in older land deeds and geographical descriptions in relevant countries.

Frequently Asked Questions

Questions About Square Kilometer (km²)

How many square meters are in a square kilometer?

There are 1,000,000 square meters in one square kilometer (1 km x 1 km = 1000 m x 1000 m).

How many square miles are in a square kilometer?

One square kilometer is approximately 0.3861 square miles.

Is km² used for small areas?

No, it's generally used for very large areas like cities or countries. Square meters, hectares, or acres are used for smaller plots.

Is km² an official SI unit?

While based on the SI unit meter, the official SI derived unit for area is the square meter (m²). However, the square kilometer is a standard metric unit widely accepted for use with SI.

About Square Mile (mi²)

How many acres are in a square mile?

There are exactly 640 acres in one square mile.

How many square feet are in a square mile?

One square mile contains 27,878,400 square feet (5280 feet x 5280 feet).

How many square kilometers are in a square mile?

One square mile is approximately 2.59 square kilometers.

Is the square mile used globally?

No, its use is primarily confined to the United States and other countries that traditionally use the imperial or US customary systems for land measurement. The square kilometer is the more common international standard for large areas.

Conversion Table: Square Kilometer to Square Mile

Square Kilometer (km²)	Square Mile (mi²)
1	0.386
5	1.931
10	3.861
25	9.653
50	19.305
100	38.61
500	193.051
1,000	386.102

All Area Conversions

Square Meter to Square Kilometer Square Meter to Square Centimeter Square Meter to Square Millimeter Square Meter to Square Inch Square Meter to Square Foot Square Meter to Square Yard Square Meter to Square Mile Square Meter to Acre Square Meter to Hectare Square Kilometer to Square Meter Square Kilometer to Square Centimeter Square Kilometer to Square Millimeter Square Kilometer to Square Inch Square Kilometer to Square Foot Square Kilometer to Square Yard Square Kilometer to Acre Square Kilometer to Hectare Square Centimeter to Square Meter Square Centimeter to Square Kilometer Square Centimeter to Square Millimeter Square Centimeter to Square Inch Square Centimeter to Square Foot Square Centimeter to Square Yard Square Centimeter to Square Mile Square Centimeter to Acre Square Centimeter to Hectare Square Millimeter to Square Meter Square Millimeter to Square Kilometer Square Millimeter to Square Centimeter Square Millimeter to Square Inch Square Millimeter to Square Foot Square Millimeter to Square Yard Square Millimeter to Square Mile Square Millimeter to Acre Square Millimeter to Hectare Square Inch to Square Meter Square Inch to Square Kilometer Square Inch to Square Centimeter Square Inch to Square Millimeter Square Inch to Square Foot Square Inch to Square Yard Square Inch to Square Mile Square Inch to Acre Square Inch to Hectare Square Foot to Square Meter Square Foot to Square Kilometer Square Foot to Square Centimeter Square Foot to Square Millimeter Square Foot to Square Inch Square Foot to Square Yard Square Foot to Square Mile Square Foot to Acre Square Foot to Hectare Square Yard to Square Meter Square Yard to Square Kilometer Square Yard to Square Centimeter Square Yard to Square Millimeter Square Yard to Square Inch Square Yard to Square Foot Square Yard to Square Mile Square Yard to Acre Square Yard to Hectare Square Mile to Square Meter Square Mile to Square Kilometer Square Mile to Square Centimeter Square Mile to Square Millimeter Square Mile to Square Inch Square Mile to Square Foot Square Mile to Square Yard Square Mile to Acre Square Mile to Hectare Acre to Square Meter Acre to Square Kilometer Acre to Square Centimeter Acre to Square Millimeter Acre to Square Inch Acre to Square Foot Acre to Square Yard Acre to Square Mile Acre to Hectare Hectare to Square Meter Hectare to Square Kilometer Hectare to Square Centimeter Hectare to Square Millimeter Hectare to Square Inch Hectare to Square Foot Hectare to Square Yard Hectare to Square Mile Hectare to Acre