Why Convert Square Miles to Square Kilometers?
Converting between square miles (mi²) and square kilometers (km²) is one of the most common area conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert mi² to km² saves time and prevents errors.
Area conversions between mi² and km² are critical for real estate valuation, agriculture, and urban planning. Farmers need accurate conversions when calculating crop yields, fertilizer application rates, or irrigation needs across hectares and acres. Homeowners and interior designers use area conversion for flooring, painting, and carpeting estimates to avoid costly material waste or shortages. In environmental science, deforestation rates and habitat protection zones are often reported in differing units depending on the region. A misunderstanding in area units can lead to significant financial discrepancies in property sales or incorrect resource allocation in land management projects.
How to Convert Square Miles to Square Kilometers
To convert square miles to square kilometers, use the following formula:
km² = mi² × 2.58998811
Example: 1 mi² = 2.58998811 km²
For example, 5 mi² = 12.94994055 km², 10 mi² = 25.8998811 km², and 100 mi² = 258.998811 km². For larger values, 1000 mi² = 2589.98811 km². Conversely, 1 km² = 0.3861021585 mi². Our calculator above performs this conversion instantly with full precision — no rounding errors.
Common Use Cases
- City area of Manhattan, NYC: 33 mi² = 85.46960764 km²
- City area of Los Angeles: 469 mi² = 1214.704424 km²
- Area of Puerto Rico: 3797 mi² = 9834.184855 km²
- One section of US public land: 1 mi² = 2.58998811 km²
Common Mistakes to Avoid
- Squaring the conversion factor: forgetting to square the linear conversion (1 ft = 12 in, but 1 sq ft = 144 sq in).
- Confusing land units: mixing up acres and hectares.
- Ignoring shape: area formulas differ for circles vs squares.
Pro Tips
- Double check squares: Always ensure you're using square units (m²), not linear (m).
- Estimation: An acre is roughly a football field (excluding end zones).
- Paint calc: 1 gallon of paint covers approx 350-400 sq ft.
What is a Square Mile?
An Imperial/US unit of area equal to 640 acres.
Used for large land areas in the US and UK.
What is a Square Kilometer?
A metric unit of area equal to 1,000,000 square meters.
Used for geographical areas of cities or countries.