Convert Square Miles to Square Kilometers
Convert Square Miles to Square Kilometers instantly. 1 Square Mile (mi²) equals 2.59 Square Kilometers (km²).
Square Miles to Square Kilometers conversion table
| Square Miles (mi²) | Square Kilometers (km²) |
|---|---|
| 1 mi² | 2.59 km² |
| 2 mi² | 5.18 km² |
| 3 mi² | 7.77 km² |
| 5 mi² | 12.9499 km² |
| 10 mi² | 25.8999 km² |
| 20 mi² | 51.7998 km² |
| 50 mi² | 129.4994 km² |
| 100 mi² | 258.9988 km² |
| 500 mi² | 1,294.99 km² |
| 1,000 mi² | 2,589.99 km² |
1 Square Mile = 2.59 Square Kilometers · multiply Square Miles by 2.59
About converting Square Miles to Square Kilometers
Square Miles (mi²) and Square Kilometers (km²) are both units of area, so converting between them is a single multiplication: multiply your Square Miles figure by 2.59. Ten Square Miles comes to 25.8999 Square Kilometers, and a hundred works out at 258.9988 Square Kilometers.
Rule of thumb: going from Square Miles to Square Kilometers multiplies, so the figure always grows — one Square Mile is already 2.59 Square Kilometers. If your answer came out smaller, you have the conversion the wrong way round.
What is a Square Mile?
A square mile is the area of a square one mile on a side, and in the United States it is the standard way to state the size of anything large: counties, states, metropolitan areas, wildfires and watersheds are all reported in square miles, along with population density in people per square mile. Elsewhere the same figure is given in square kilometers, which is why one lake can carry two very different-looking numbers depending on the source. The unit is literally built into the American landscape — the Public Land Survey System carved much of the country into square-mile sections, which is why the Midwest is a grid of mile-spaced roads.
What is a Square Kilometer?
A square kilometer is the area of a square one kilometer on a side, and it is how the world reports anything from the size of a town upward: city footprints, lakes, national parks, forest lost to fire, the areas of countries. Its classic trap is that the prefix is squared along with the unit — both sides of the square grow by a thousand, so the area grows by that factor twice over, and people who expect a simple thousand-fold jump land three orders of magnitude out. The same squaring is why a map at twice the scale covers four times the ground.
To put both in perspective: Manhattan is roughly 23 square miles, while Central Park in New York is about 3.4 square kilometers.
The converter above updates as you type, and the table lists common values for quick reference. Need the opposite direction? Use the Square Kilometers to Square Miles converter, or browse all Area converters.
Frequently asked questions
How many Square Kilometers are in one Square Mile?
There are 2.59 Square Kilometers in one Square Mile.
How do I convert Square Miles to Square Kilometers?
Multiply the number of Square Miles by 2.59. For example, 10 Square Miles = 25.8999 Square Kilometers.
What is 100 Square Miles in Square Kilometers?
100 Square Miles is equal to 258.9988 Square Kilometers.
How do I convert Square Kilometers to Square Miles?
Multiply the Square Kilometers value by 0.3861 (or divide by 2.59).
Is this Square Miles to Square Kilometers conversion exact?
The definition is exact — Square Miles and Square Kilometers are both fixed against the same base by international agreement — but the decimal shown here is rounded for readability, because the true ratio does not terminate. For engineering or scientific work, carry more decimal places than this page displays.
What is a Square Mile?
A square mile is the area of a square one mile on a side, and in the United States it is the standard way to state the size of anything large: counties, states, metropolitan areas, wildfires and watersheds are all reported in square miles, along with population density in people per square mile. Elsewhere the same figure is given in square kilometers, which is why one lake can carry two very different-looking numbers depending on the source. The unit is literally built into the American landscape — the Public Land Survey System carved much of the country into square-mile sections, which is why the Midwest is a grid of mile-spaced roads.
What is a Square Kilometer?
A square kilometer is the area of a square one kilometer on a side, and it is how the world reports anything from the size of a town upward: city footprints, lakes, national parks, forest lost to fire, the areas of countries. Its classic trap is that the prefix is squared along with the unit — both sides of the square grow by a thousand, so the area grows by that factor twice over, and people who expect a simple thousand-fold jump land three orders of magnitude out. The same squaring is why a map at twice the scale covers four times the ground.