Convert Square Miles (mi²) to Square Kilometers (km²)
1 square mile equals 2.58999 square kilometers.
Square Mile to Square Kilometer Converter
How to Convert Square Mile to Square Kilometer
1 square mile = 2.58999 square kilometers exact
Square Kilometer = Square Mile × 2.58999
Example: 1 mi² × 2.58999 = 2.58999 km²
Reverse Conversion
To convert square kilometers back to square miles:
- Remember, 1 square kilometer equals 0.386102 square miles.
- To convert 2.58999 km² to mi², multiply
2.58999 x 0.386102, resulting in1 mi².
exact This conversion factor is exact by international definition.
Common Square Mile to Square Kilometer Conversions
| Square Mile | Square Kilometer | Actions |
|---|---|---|
| 1 square mile | 2.58999 square kilometers | |
| 5 square miles | 12.9499 square kilometers | |
| 10 square miles | 25.8999 square kilometers |
| Square Mile | Square Kilometer | Actions |
|---|---|---|
| 50 square miles | 129.499 square kilometers | |
| 100 square miles | 258.999 square kilometers |
Square miles to square kilometers Conversion Table
Reference table with common square miles to square kilometers conversions. All values calculated with high precision.
Square Miles to Square Kilometers Table
0.0001 to 12
Square Miles to Square Kilometers Table
1 to 100000
Square Kilometers to Square Miles Table
0.001 to 5
Square Kilometers to Square Miles Table
10 to 1000000
Definition of Square Mile
- Definition
-
mi² — The square mile is a unit of area in the US customary and British imperial systems. It is defined as the area of a square with sides of exactly 1 statute mile (1,609.344 meters), giving an exact metric equivalent of 2,589,988.110336 m².
The square mile is the standard unit for expressing large land areas in the United States and the United Kingdom, commonly used in geography, census data, real estate for large tracts, and municipal planning.
One square mile equals exactly 640 acres, a relationship established by statute. It also equals exactly 3,097,600 square yards or 27,878,400 square feet.
- Exact factor
- 1 mi² = 2,589,988.110336 m²
- Examples
-
- 7 mi² = 195,148,800 ft²
- 0.84 mi² = 537.6 ac
- 5.2 mi² = 13.468 km²
Definition of Square Kilometer
- Definition
-
km² — The square kilometer is an SI-derived unit of area equal to exactly 1,000,000 m² (one million square meters). It represents the area of a square with sides of 1 kilometer.
The square kilometer is the standard unit for expressing large geographic areas such as countries, states, cities, lakes, national parks, and ecological regions. It is used globally in geography, cartography, and environmental science.
One square kilometer equals exactly 100 hectares or 10,000 ares. These relationships are exact because all three units are defined as powers of ten of the square meter.
- Exact factor
- 1 km² = 1,000,000 m²
- Examples
-
- 5,300 km² = 5,300,000,000 m²
- 5,300 km² = 57,048,725,209 ft²
- 39 km² = 15.058 mi²
About the Square Mile
Facts & Uses
- 1 mi² = 2.589988110336 km² exactly = 640 acres. The standard US/UK unit for large geographic areas.
- Standard in US geography: state and county sizes, national park areas, urban land use, agricultural surveys.
- Used in US Census data for population density (people/mi²), weather coverage areas, and federal land management.
- Reference: Manhattan is about 22.8 mi²; Los Angeles ≈ 469 mi²; Texas ≈ 268,597 mi²; Alaska ≈ 663,267 mi².
Curiosities
- The US Public Land Survey System (PLSS) divides land into 36-square-mile townships, each township subdivided into 36 sections of 1 mi² (640 acres) — the basis for rural land descriptions in 30+ states.
- The Great Lakes have a combined surface area of about 94,250 mi² (244,106 km²) — more than the entire UK.
- 1 mi² = 640 acres exactly — a clean number because the acre was historically defined as 1/640 of a square mile in the colonial English land system.
- Approximate equivalents: 1 mi² ≈ 2.59 km² = 640 acres = 27,878,400 ft².
Sources
About the Square Kilometer
Facts & Uses
- 1 km² = 1,000,000 m² exactly = 100 hectares. The metric unit for large geographic areas: cities, countries, lakes, forests.
- Standard in geography (country and region sizes), environmental science (deforestation, conservation areas), and urban planning.
- Used in satellite imagery analysis, land use statistics, and population density (people per km²).
- Reference scales: 1 km² ≈ small village, 100 km² ≈ small town, 1000 km² ≈ large metropolitan core, 1,000,000 km² ≈ medium-sized country.
Curiosities
- Vatican City is the smallest country at 0.49 km²; Russia is the largest at over 17 million km². Earth's total surface is about 510 million km² (71% ocean).
- The Amazon rainforest covers approximately 5.5 million km² across nine countries — about the size of the contiguous US west of the Mississippi.
- Population density extremes: Monaco ~26,000 people/km²; Mongolia ~2 people/km² — a 13,000× difference.
- Approximate equivalents: 1 km² ≈ 0.386 mi² ≈ 247 acres ≈ 100 hectares.
Sources
Frequently Asked Questions
How many square kilometers are in one square mile?
One square mile equals 2.58999 square kilometers. To convert, multiply the square mile value by 2.58999. For the reverse, divide the square kilometer value by 2.58999 (or multiply by 0.386102).
What is 0.17 square miles in square kilometers?
0.17 square miles = 0.4403 square kilometers. This is one of the most commonly searched conversions for this pair.
How precise is the square mile-to-square kilometer conversion?
The factor 2.58999 is accurate to 6 significant figures, derived from international measurement standards. Our calculator uses full precision internally.
Looking for the reverse? Convert Square Kilometer to Square Mile
Related Area Converters
Explore other area conversion tools:
