Acre (US Survey) to Hectare Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Acre (US Survey) to Hectare
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)) = 0.404687261 Hectare (ha).
Acre (US Survey) to Hectare — Common Values
| Acre (US Survey) (ac (US)) | Hectare (ha) |
|---|---|
| 0.1 | 0.0404687261 |
| 0.5 | 0.2023436305 |
| 1 | 0.404687261 |
| 2 | 0.809374522 |
| 5 | 2.023436305 |
| 10 | 4.04687261 |
| 25 | 10.11718152 |
| 50 | 20.23436305 |
| 100 | 40.4687261 |
| 500 | 202.3436305 |
| 1000 | 404.687261 |
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 Hectare (ha)
Definition
The hectare is a metric unit of area equal to 10,000 square meters, or 100 ares — the area of a square 100 meters on each side.
Mathematical Relationship
1 ha = 10,000 m² = 100 a = 0.01 km² ≈ 2.471 acres.
Conversion Formula
To convert ha to acres: multiply by 2.471. To km²: divide by 100. To m²: multiply by 10,000.
Practical Applications
Farm sizes, vineyard areas, forestry management, urban planning zones, and national park boundaries.
Interesting Facts
Singapore has a total area of about 72,800 ha. The Amazon rainforest loses about 1 million ha per year to deforestation.
Common Mistakes
Confusing hectare with acre — a hectare is about 2.47 acres, not equal to one. Also, 1 km² = 100 ha, not 1,000.
Educational Tips
A hectare = 100 m × 100 m. A football field is about 0.7 ha. Two football fields ≈ 1.4 ha — close to 1 ha.