Converting Acres to Hectares (ac to ha)
Converting acres to hectares (ac to ha) is the primary bridge between the Anglo-American Customary land measurement system and the International Metric standard.
While farmland, ranches, and residential lots across the United States, United Kingdom, and Canada are listed in statute acres, international trade reports, United Nations environmental data, and European Union agricultural treaties record land exclusively in hectares.
Under the 1959 International Yard and Pound Agreement recognized by the National Institute of Standards and Technology (NIST Handbook 44) and the BIPM, one international statute acre equals exactly 4,046.8564224 square meters, or 0.40468564224 hectares.
Whether you are comparing global farm productivity, assessing overseas real estate investments, or reviewing a carbon credit forestry tract, our reciprocal Hectares to Acres Converter and universal Area Converter Hub guarantee certified calculation accuracy.
Historical Origins of the Acre and the Metric Hectare
The term acre originates from the Old English æcer, representing the amount of land a yoke of oxen could plow in a single day under the medieval open-field system.
In 1297, King Edward I of England codified the statutory acre as a rectangular strip measuring 40 rods (one furlong, or 660 feet) in length by 4 rods (one chain, or 66 feet) in width, establishing the modern area of 43,560 square feet.
In contrast, the French metric system established the hectare in 1795 as a rational decimal square measuring 100 meters by 100 meters (10,000 square meters), eliminating regional feudal discrepancies.
Because one hectare contains 10,000 square meters and one acre contains 4,046.86 square meters, a hectare is approximately 2.471 times larger than an acre.
Exact Mathematical Formulas for Acres to Hectares
To convert any surveyed acre measurement into metric hectares, multiply the acre total by 0.40468564224.
Step-by-Step Practical Calculation Examples
Let us review three practical real estate and farm conversions:
- Example 1: Converting a 2.5-Acre Rural Homestead
Hectares = 2.5 × 0.40468564 = 1.0117 Hectares (roughly 1 full hectare). - Example 2: Converting a 40-Acre Quarter-Quarter Farm Section
Hectares = 40 × 0.40468564 = 16.1874 Hectares. - Example 3: Converting a 640-Acre Full Land Section (1 Square Mile)
Hectares = 640 × 0.40468564 = 258.9988 Hectares (2.59 km²).
Land Parcel & Farm Acreage Reference Table
Use this reference table to look up exact hectare equivalents for land parcels ranging from a quarter-acre up to 10,000 acres.
| Acreage (ac) | Hectares (ha) | Square Meters (m²) | Typical Property Application |
|---|---|---|---|
| 0.25 Acre | 0.1012 ha | 1,011.71 m² | Suburban single-family residential lot |
| 0.50 Acre | 0.2023 ha | 2,023.43 m² | Semi-rural residential lot / Executive home |
| 1.00 Acre | 0.4047 ha | 4,046.86 m² | Statutory acre benchmark / Micro-homestead |
| 2.471 Acres | 1.0000 ha | 10,000.00 m² | Exact 1-Hectare metric parcel equivalent |
| 5.00 Acres | 2.0234 ha | 20,234.28 m² | Smallholding / Equestrian pasture lot |
| 10.00 Acres | 4.0469 ha | 40,468.56 m² | Hobby farm / Commercial nursery / Vineyard |
| 20.00 Acres | 8.0937 ha | 80,937.13 m² | Commercial orchard / Solar energy field |
| 40.00 Acres | 16.1874 ha | 161,874.26 m² | US Public Land Survey quarter-quarter section |
| 100.00 Acres | 40.4686 ha | 404,685.64 m² | Medium commercial crop farm / Livestock pasture |
| 160.00 Acres | 64.7497 ha | 647,497.03 m² | Quarter Section (Historic US Homestead Act grant) |
| 640.00 Acres | 258.9988 ha | 2,589,988.11 m² | Full 1 Square Mile Section (2.59 km²) |
| 1,000.00 Acres | 404.6856 ha | 4,046,856.42 m² | Large commercial agriculture / Timber concession |
Agricultural Yields: Bushels per Acre to Tonnes per Hectare
Agricultural commodity traders regularly convert crop yields between US customary units (bushels per acre) and international metric standards (metric tonnes per hectare).
For corn (maize), one bushel weighs 56 pounds (25.401 kg). A US corn yield of 180 bushels per acre translates to approximately 11.30 metric tonnes per hectare (1.13 kg/m²).
For soybeans and wheat, one bushel weighs 60 pounds (27.216 kg). A wheat harvest yielding 60 bushels per acre equals approximately 4.04 metric tonnes per hectare.
By converting land boundaries into hectares, international grain producers can benchmark production costs against South American and European competitors on an identical metric footing.
Agricultural Crop Yield Conversion Matrix
The table below provides direct yield conversion multipliers for primary grain and oilseed crops.
| Crop Type | Bushel Weight (lbs / kg) | US Yield (bu/acre) | Metric Yield (t/ha) |
|---|---|---|---|
| Corn / Maize | 56 lbs (25.40 kg) | 180 bu/ac | 11.30 tonnes/ha |
| Soybeans | 60 lbs (27.22 kg) | 50 bu/ac | 3.36 tonnes/ha |
| Wheat | 60 lbs (27.22 kg) | 60 bu/ac | 4.04 tonnes/ha |
| Barley | 48 lbs (21.77 kg) | 80 bu/ac | 4.30 tonnes/ha |
| Oats | 32 lbs (14.51 kg) | 90 bu/ac | 3.23 tonnes/ha |
Global Land Area Units & Conversion Factor Hierarchy
The table below summarizes the exact mathematical relationship between statute acres, metric hectares, and international surface units.
| Unit Name | Equivalent in Acres | Equivalent in Hectares | Measurement System |
|---|---|---|---|
| Square Foot (sq ft) | 0.0000229568 ac | 0.0000092903 ha | US Customary / Imperial |
| Square Yard (sq yd) | 0.0002066116 ac | 0.0000836127 ha | Imperial Area |
| Square Meter (m²) | 0.0002471054 ac | 0.000100 ha | Base SI Metric Unit |
| Statute Acre (ac) | 1.0000 ac | 0.404686 ha | US/UK Cadastral Standard |
| Hectare (ha) | 2.471054 ac | 1.0000 ha | Global Metric Land Standard |
| Square Mile (sq mi) | 640.0000 ac | 258.9988 ha | US Land Section (2.59 km²) |
Frequently Asked Questions About Acres to Hectares
How many hectares are in one acre?
One international statute acre equals exactly 0.40468564224 hectares (approximately 0.4047 ha). One acre represents about 40.47% of a standard metric hectare.
What is the mathematical formula to convert acres to hectares?
The formula is: Hectares = Acres × 0.40468564 (or Hectares = Acres ÷ 2.4710538). For instance, converting 20 acres yields 20 × 0.40468564 = 8.0937 Hectares.
How many hectares is 5 acres and 10 acres?
5 acres equals 2.0234 hectares (20,234.3 m²). 10 acres equals 4.0469 hectares (40,468.6 m²).
How do I convert hectares back to acres?
To reverse the calculation, multiply hectares by 2.4710538: Acres = Hectares × 2.4710538. You can also use our dedicated Hectares to Acres Converter for instant calculations.
Which unit is larger: an acre or a hectare?
A hectare is much larger than an acre. One hectare equals 10,000 square meters (2.471 acres), whereas one acre equals 4,046.86 square meters. A hectare is roughly 2.47 times the size of an acre.
How many hectares are in 100 acres?
100 acres equals exactly 40.4686 hectares (404,685.6 m²).
How many hectares are in a square mile (640 acres)?
One square mile contains 640 acres, which equals exactly 258.9988 hectares (approximately 2.59 square kilometers).