Acre (US Survey) to Circular Inch Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Acre (US Survey) to Circular Inch
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)) = 7986605.246 Circular Inch (circ in).
Acre (US Survey) to Circular Inch — Common Values
| Acre (US Survey) (ac (US)) | Circular Inch (circ in) |
|---|---|
| 0.1 | 798660.5246 |
| 0.5 | 3993302.623 |
| 1 | 7986605.246 |
| 2 | 15973210.49 |
| 5 | 39933026.23 |
| 10 | 79866052.46 |
| 25 | 199665131.1 |
| 50 | 399330262.3 |
| 100 | 798660524.6 |
| 500 | 3993302623 |
| 1000 | 7986605246 |
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 Circular Inch (circ in)
Definition
The circular inch is the area of a circle one inch in diameter, equal to π/4 square inches (approximately 0.0005067 m²).
Mathematical Relationship
1 circular inch = π/4 in² ≈ 0.7854 in² ≈ 5.067 cm². Equals 1,000,000 circular mils.
Conversion Formula
To convert circular inches to in²: multiply by 0.7854. To cm²: multiply by 5.067.
Practical Applications
Wire and cable cross-section calculations, especially for large conductors in power distribution.
Interesting Facts
The circular mil and circular inch exist solely to avoid π in cross-section math. Diameter² (in circular units) directly gives the area.
Common Mistakes
Confusing circular inch with square inch — a circular inch is about 78.5% of a square inch.
Educational Tips
For a circle: area in circular inches = diameter². Area in square inches = diameter² × π/4. The circular unit absorbs the π/4 factor.