UnitConvConvert
Area

Convert square kilometers to square miles

1 km²=0.3861mi²

Use the converter below to change any square kilometers value into square miles instantly — with formula, conversion table, and real-world examples.

0.3861

Conversion formula

Forward
square miles = square kilometers × 0.3861
Reverse
square kilometers = square miles × 2.58999

Example: 10 km² × 0.3861 = 3.86102 mi².

About both units

From

Square Kilometer

km²

The square kilometre equals 1,000,000 m² or 100 hectares. It is used for city, region and country areas. Greater London is about 1572 km². The smallest sovereign countries (Monaco, Vatican City) are under 3 km² each.

Real-world: Greater London is 1572 km². France is 643,801 km². The Serengeti National Park is 14,763 km².
Read full square kilometer reference →
To

Square Mile

mi²

The square mile equals 2.589988 square kilometres. It is used for US and UK geographic areas — city, county, state and country sizes. Greater London is 607 mi²; the US state of Texas is 268,597 mi².

Real-world: New York City is 302.6 mi². Texas is 268,597 mi². Greater London is 607 mi².
Read full square mile reference →

Square Kilometer to Square Mile conversion table

Common square kilometers to square miles values for quick reference.

Square Kilometer (km²)Square Mile (mi²)
1 km²0.3861 mi²
5 km²1.93051 mi²
10 km²3.86102 mi²
50 km²19.3051 mi²
100 km²38.6102 mi²
500 km²193.051 mi²
1,000 km²386.102 mi²
5,000 km²1,930.51 mi²
10,000 km²3,861.02 mi²
50,000 km²19,305.11 mi²

Tips & common mistakes

Quick tips

  • 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.

Avoid these

  • 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.

Frequently asked questions

How many square miles in a square kilometer?
One square kilometer equals 0.3861 square miles.
How do I convert square kilometers to square miles?
Multiply the square kilometer value by 0.3861 to get the equivalent in square miles.
What is 100 square kilometers in square miles?
100 square kilometers equals 38.6102 square miles.
Is a square kilometer bigger than a square mile?
No. 1 square kilometer equals 0.3861 square miles, so one square kilometer is smaller.
How to convert square kilometers to square miles without a calculator?
Multiply by 0.39 for a quick estimate; use a calculator for precise results.

Related area conversions

📊 See full comparison matrix →

More from Square Kilometer

km² → m²
1 = 1,000,000 m²
km² → cm²
1 = 10,000,000,000 cm²
km² → mm²
1 = 1,000,000,000,000 mm²
km² → ha
1 = 100 ha
km² → ac
1 = 247.105 ac
km² → ft²
1 = 10,763,910.42 ft²
km² → in²
1 = 1,550,003,100.01 in²
km² → yd²
1 = 1,195,990.05 yd²

More to Square Mile

m² → mi²
1 = 3.8610e-7 mi²
cm² → mi²
1 = 3.8610e-11 mi²
mm² → mi²
1 = 3.8610e-13 mi²
ha → mi²
1 = 0.003861 mi²
ac → mi²
1 = 0.001563 mi²
ft² → mi²
1 = 3.5870e-8 mi²
in² → mi²
1 = 2.4910e-10 mi²
yd² → mi²
1 = 3.2283e-7 mi²

Conversions in other categories

WeightKilogram → PoundLengthKilometer → MileTemperatureCelsius → FahrenheitVolumeLiter → US GallonSpeedKilometer per Hour → Mile per HourEnergyKilojoule → KilocaloriePressureBar → Pound per Square InchPowerKilowatt → Mechanical Horsepower