Convert Square Miles to Square Kilometers

Convert Square Miles (mi²) to Square Kilometers (km²) instantly and accurately.

Square Miles (mi²)
Square Kilometers (km²)

Conversion Formula

km² = mi² × 2.58998811

About Square Miles

A square mile (mi²) is an imperial unit of area equal to a square with sides of one mile (5,280 ft × 5,280 ft). It is used for measuring large land areas like counties, states, and countries in the United States. Los Angeles covers about 503 mi², Rhode Island (smallest US state) is roughly 1,214 mi², and Alaska is about 665,384 mi². This unit is standard in American geography, land surveying, and regional planning.

About Square Kilometers

A square kilometer (km²) is a metric unit of area equal to a square with sides of one kilometer (1,000 m × 1,000 m). It is used for measuring large land areas such as cities, forests, lakes, and countries. Manhattan (New York) is about 59 km², and Monaco (the second smallest country) is just over 2 km². This unit is essential in geography, urban planning, forestry, and environmental impact studies.

Quick Reference Table

Square Miles (mi²)Square Kilometers (km²)
1 mi²2.58999 km²
2 mi²5.17998 km²
5 mi²12.9499 km²
10 mi²25.8999 km²
25 mi²64.7497 km²
50 mi²129.499 km²
100 mi²258.999 km²

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