Square Mile (US Survey) to Square Kilometer Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Square Mile (US Survey) to Square Kilometer
To convert US survey mi² to km²: multiply by 2.590. To international mi²: multiply by ~1.000004.
1 mi² (US) ≈ 2,589,998.47 m². Differs from international mi² (2,589,988.11 m²) by about 10.36 m².
For example, 1 Square Mile (US Survey) (mi² (US)) = 2.58999847 Square Kilometer (km²).
Square Mile (US Survey) to Square Kilometer — Common Values
| Square Mile (US Survey) (mi² (US)) | Square Kilometer (km²) |
|---|---|
| 0.1 | 0.258999847 |
| 0.5 | 1.294999235 |
| 1 | 2.58999847 |
| 2 | 5.179996941 |
| 5 | 12.94999235 |
| 10 | 25.8999847 |
| 25 | 64.74996176 |
| 50 | 129.4999235 |
| 100 | 258.999847 |
| 500 | 1294.999235 |
| 1000 | 2589.99847 |
About Square Mile (US Survey) (mi² (US))
Definition
The US survey square mile is a historical area unit based on the US survey foot, equal to approximately 2,589,998.47 m².
Mathematical Relationship
1 mi² (US) ≈ 2,589,998.47 m². Differs from international mi² (2,589,988.11 m²) by about 10.36 m².
Conversion Formula
To convert US survey mi² to km²: multiply by 2.590. To international mi²: multiply by ~1.000004.
Practical Applications
Historical US Public Land Survey System sections (each nominally 1 mi² US survey).
Interesting Facts
Over one square mile, the US survey definition differs from the international definition by about 10.4 m² — roughly a 3 m × 3.5 m room.
Common Mistakes
Using the US survey mile for new calculations. Deprecated since 2023 — use the international definitions.
Educational Tips
The US Survey system was a legacy from 1893. Its 2023 retirement unified US measurements with the international standard.
About Square Kilometer (km²)
Definition
The square kilometer is a metric unit of area equal to 1,000,000 square meters, or a square with sides of 1 kilometer.
Mathematical Relationship
1 km² = 1,000,000 m² = 100 ha = 247.105 acres ≈ 0.3861 mi².
Conversion Formula
To convert km² to mi²: multiply by 0.3861. To hectares: multiply by 100. To acres: multiply by 247.105.
Practical Applications
Country areas, national park sizes, city footprints, forest coverage, and watershed boundaries.
Interesting Facts
Vatican City = 0.44 km². Manhattan = 59.1 km². Russia = 17,098,242 km² (largest country). Earth's surface = 510,072,000 km².
Common Mistakes
Thinking 1 km² = 1,000 m² (it's actually 1,000,000 m²). Area scales as the square of the linear dimension.
Educational Tips
1 km = 1,000 m, but 1 km² = 1,000² m² = 1,000,000 m². Always square the conversion factor for area.