Section to Acre (US Survey) Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Section to Acre (US Survey)
To convert sections to acres: multiply by 640. To km²: multiply by 2.59.
1 section = 1 mi² = 640 acres = 2.59 km². 36 sections = 1 township.
For example, 1 Section (section) = 639.99744 Acre (US Survey) (ac (US)).
Section to Acre (US Survey) — Common Values
| Section (section) | Acre (US Survey) (ac (US)) |
|---|---|
| 0.1 | 63.999744 |
| 0.5 | 319.99872 |
| 1 | 639.99744 |
| 2 | 1279.99488 |
| 5 | 3199.9872 |
| 10 | 6399.9744 |
| 25 | 15999.936 |
| 50 | 31999.872 |
| 100 | 63999.744 |
| 500 | 319998.72 |
| 1000 | 639997.44 |
About Section (section)
Definition
A section is a unit of land area equal to 1 square mile (640 acres or 2.59 km²), used in the US Public Land Survey System.
Mathematical Relationship
1 section = 1 mi² = 640 acres = 2.59 km². 36 sections = 1 township.
Conversion Formula
To convert sections to acres: multiply by 640. To km²: multiply by 2.59.
Practical Applications
Rural property descriptions, agricultural land division, mineral rights, and road grid planning in the western US.
Interesting Facts
Section 16 in every township was traditionally reserved for public schools — a major source of early American education funding.
Common Mistakes
Forgetting that sections are numbered in a specific serpentine pattern within a township (1 in NE, snaking to 36).
Educational Tips
The US west of Ohio is largely divided into a grid of 1-mile sections. Look at Google Maps in rural areas to see the grid patterns.
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.