Square Foot (US Survey) to Acre Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Square Foot (US Survey) to Acre
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)) = 0.00002295693297 Acre (ac).
Square Foot (US Survey) to Acre — Common Values
| Square Foot (US Survey) (ft² (US)) | Acre (ac) |
|---|---|
| 0.1 | 0.000002295693297 |
| 0.5 | 0.00001147846648 |
| 1 | 0.00002295693297 |
| 2 | 0.00004591386593 |
| 5 | 0.0001147846648 |
| 10 | 0.0002295693297 |
| 25 | 0.0005739233242 |
| 50 | 0.001147846648 |
| 100 | 0.002295693297 |
| 500 | 0.01147846648 |
| 1000 | 0.02295693297 |
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 (ac)
Definition
The acre is a unit of area equal to 43,560 square feet (4,046.86 m²), historically the area a team of oxen could plow in one day.
Mathematical Relationship
1 acre = 43,560 ft² = 4,840 yd² = 4,046.86 m² ≈ 0.4047 ha. 640 acres = 1 mi².
Conversion Formula
To convert acres to hectares: multiply by 0.4047. To m²: multiply by 4,046.86. To ft²: multiply by 43,560.
Practical Applications
Real estate listings, farmland area, lot sizes, park acreages, and zoning regulations.
Interesting Facts
A US football field (including end zones) is about 1.32 acres. Central Park in NYC is 843 acres. An acre is about 75% of a football field.
Common Mistakes
Thinking an acre is a square shape — it can be any shape with the right total area. Also, confusing acre with hectare (1 acre ≈ 0.4 ha).
Educational Tips
Imagine a football field without the end zones — that's roughly 1 acre. Or 16 tennis courts side by side.