Hectare to Acre (US Survey) Converter
Unit Converter
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23 units available
6 categories total
How to Convert Hectare to Acre (US Survey)
To convert ha to acres: multiply by 2.471. To km²: divide by 100. To m²: multiply by 10,000.
1 ha = 10,000 m² = 100 a = 0.01 km² ≈ 2.471 acres.
For example, 1 Hectare (ha) = 2.47104393 Acre (US Survey) (ac (US)).
Hectare to Acre (US Survey) — Common Values
| Hectare (ha) | Acre (US Survey) (ac (US)) |
|---|---|
| 0.1 | 0.247104393 |
| 0.5 | 1.235521965 |
| 1 | 2.47104393 |
| 2 | 4.942087861 |
| 5 | 12.35521965 |
| 10 | 24.7104393 |
| 25 | 61.77609826 |
| 50 | 123.5521965 |
| 100 | 247.104393 |
| 500 | 1235.521965 |
| 1000 | 2471.04393 |
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.
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.