Acre (US Survey) to Square Mile Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Acre (US Survey) to Square Mile
To convert US survey acres to m²: multiply by 4,046.873. To international acres: multiply by ~1.000004.
1 US survey acre ≈ 4,046.873 m². Differs from international acre (4,046.856 m²) by about 0.016 m².
For example, 1 Acre (US Survey) (ac (US)) = 0.00156250625 Square Mile (mi²).
Acre (US Survey) to Square Mile — Common Values
| Acre (US Survey) (ac (US)) | Square Mile (mi²) |
|---|---|
| 0.1 | 0.000156250625 |
| 0.5 | 0.000781253125 |
| 1 | 0.00156250625 |
| 2 | 0.0031250125 |
| 5 | 0.00781253125 |
| 10 | 0.0156250625 |
| 25 | 0.03906265625 |
| 50 | 0.0781253125 |
| 100 | 0.156250625 |
| 500 | 0.781253125 |
| 1000 | 1.56250625 |
About Acre (US Survey) (ac (US))
Definition
The US survey acre is a historical unit of area based on the US survey foot, equal to approximately 4,046.873 m².
Mathematical Relationship
1 US survey acre ≈ 4,046.873 m². Differs from international acre (4,046.856 m²) by about 0.016 m².
Conversion Formula
To convert US survey acres to m²: multiply by 4,046.873. To international acres: multiply by ~1.000004.
Practical Applications
Historical US land surveys, old property deeds, and State Plane Coordinate System calculations.
Interesting Facts
The difference between US survey and international acre is about 0.016 m² — roughly the area of a sheet of paper. Over large areas, it adds up.
Common Mistakes
Using US survey acre in new calculations — it's been deprecated since 2023. Use the international acre instead.
Educational Tips
As of 2023, the US survey foot and acre are retired. All US measurements now use the international definitions.
About Square Mile (mi²)
Definition
The square mile is an imperial unit of area equal to the area of a square with sides of one mile (2.59 km²).
Mathematical Relationship
1 mi² = 640 acres = 27,878,400 ft² = 2.59 km² = 259 ha.
Conversion Formula
To convert mi² to km²: multiply by 2.59. To acres: multiply by 640. To hectares: multiply by 259.
Practical Applications
City areas, county sizes, population density, land surveys, and geographic comparisons.
Interesting Facts
Manhattan is about 22.8 mi². The state of Texas is 268,596 mi². Rhode Island (smallest US state) is 1,214 mi².
Common Mistakes
1 mi ≈ 1.609 km, but 1 mi² ≈ 2.59 km² (not 1.609). Area conversion squares the factor.
Educational Tips
1 mi² = 640 acres. This 'section' (640 acres) is the basis of the US Public Land Survey System grid.