Convert Square Kilometer to Square Mile (km² → mi²)

Converting square kilometers to square miles is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in square kilometers

   Start with the number of square kilometers (km²) you want to convert.
2. 2
   Multiply by 0.386102

   The conversion factor from km² to mi² is 0.386102. Multiply your value by this number.
3. 3
   Read the result in square miles

   The result is your value in square miles (mi²).

Multiply the value in square kilometers by 0.386102. For the reverse direction, multiply by 2.589988.

• ✓1 km² = 100 hectares = 1,000,000 m².
• ✓1 km² = 0.386 square miles.
• ✓Multiply km × km in metric to get km² — but always keep consistent units.

• ✗Mixing km² and km when comparing geography — 10 km is a length, 10 km² is an area.
• ✗Confusing km² with the square mile (mi²) in international comparisons.
• ✗Reading "million km²" as "km²" on continental-scale maps — factor of 10⁶.

What is the Square Kilometer?

The square kilometer equals 1,000,000 square meters (or 100 hectares) and is the international standard for measuring large areas: cities, national parks, lakes, watersheds, and country-level statistics. Population density is conventionally given in people per km² (e.g., Singapore has roughly 8,400 people/km², Mongolia has fewer than 2). The largest US national park, Wrangell-St. Elias in Alaska, covers about 53,000 km². France is 643,801 km², and the largest country, Russia, spans 17 million km². The square kilometer relates to the square meter (1 km² = 1,000,000 m²), the hectare (1 km² = 100 ha), the square mile (1 km² ≈ 0.386 mi²), and the acre (1 km² ≈ 247.1 acres). Geographic information systems, climate science, and regional planning all rely on square kilometers as the base unit for area.

• Country and city geographic area reporting
• National-park and protected-area sizes
• Large-scale environmental studies (deforestation, etc.)

What is the Square Mile?

The square mile equals exactly 2.589988110336 square kilometers (or 640 acres) and is the American unit for measuring large geographic areas: counties, states, watersheds, and large parks. The continental United States covers about 3 million square miles, and Texas alone is 268,597 mi². Population density in US contexts is given in people per square mile (e.g., New York City has about 27,000 people/mi²). The square mile relates to the acre (640 acres = 1 mi²), the square kilometer (1 mi² ≈ 2.59 km²), the square foot (1 mi² = 27,878,400 ft²), and the hectare (1 mi² ≈ 259 ha). It is the natural large-area unit for American geographic discussion, though metric countries use square kilometers for the same purpose.

• US states, counties and cities
• UK geographic and historical boundaries
• Large estate and national-park reporting in Anglo contexts