Square Foot (US Survey) to Acre (US Survey) Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Square Foot (US Survey) to Acre (US Survey)
To convert US survey ft² to m²: multiply by 0.09290341. To international ft²: multiply by ~1.000004.
1 ft² (US) ≈ 0.09290341 m². Differs from international ft² (0.09290304 m²) by about 4 × 10⁻⁷ m².
For example, 1 Square Foot (US Survey) (ft² (US)) = 0.00002295684114 Acre (US Survey) (ac (US)).
Square Foot (US Survey) to Acre (US Survey) — Common Values
| Square Foot (US Survey) (ft² (US)) | Acre (US Survey) (ac (US)) |
|---|---|
| 0.1 | 0.000002295684114 |
| 0.5 | 0.00001147842057 |
| 1 | 0.00002295684114 |
| 2 | 0.00004591368228 |
| 5 | 0.0001147842057 |
| 10 | 0.0002295684114 |
| 25 | 0.0005739210285 |
| 50 | 0.001147842057 |
| 100 | 0.002295684114 |
| 500 | 0.01147842057 |
| 1000 | 0.02295684114 |
About Square Foot (US Survey) (ft² (US))
Definition
The US survey square foot is a historical area unit based on the US survey foot (1200/3937 m), equal to approximately 0.09290341 m².
Mathematical Relationship
1 ft² (US) ≈ 0.09290341 m². Differs from international ft² (0.09290304 m²) by about 4 × 10⁻⁷ m².
Conversion Formula
To convert US survey ft² to m²: multiply by 0.09290341. To international ft²: multiply by ~1.000004.
Practical Applications
Historical property records and government land survey documents.
Interesting Facts
The difference from the international square foot is only about 0.4 mm² — negligible for a single measurement, but significant over millions of square feet.
Common Mistakes
Using the US survey foot in new work. Since 2023, only the international foot is valid in the US.
Educational Tips
The US survey foot existed because of a historical definition difference. It's now retired — use the international foot (exactly 0.3048 m).
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.