Acres to Hectares Converter (ac to ha)
Convert acres to hectares for farms, ranches and land deals. 1 acre = 0.404686 ha, so 5 acres is 2.02 hectares and 640 acres (one square mile) is 259 hectares.
Real-World Benchmarks
Multi-Unit Conversion Matrix
| Group | Measurement | Symbol | Equivalent Value |
|---|---|---|---|
| Metric (SI) | Square Millimeter | mm² | 2.0234E10 |
| Metric (SI) | Square Centimeter | cm² | 2.0234E8 |
| Metric (SI) | Square Meter | m² | 20,234.2821 |
| Metric (SI) | Are | a | 202.3428 |
| Metric (SI) | Hectare | ha | 2.0234 |
| Metric (SI) | Square Kilometer | km² | 0.0202 |
| Imperial & US Customary | Square Inch | in² | 3.1363E7 |
| Imperial & US Customary | Square Foot | ft² | 217,800 |
| Imperial & US Customary | Square Yard | yd² | 24,200 |
| Imperial & US Customary | Acre | ac | 5 |
| Imperial & US Customary | Square Mile | mi² | 0.0078 |
Step-by-Step Mathematical Explanation
- Step 1: Convert 5 ac to the base unit (m²): 5 × 4,046.8564224 = 20,234.282112 m².
- Step 2: Convert base square meters to hectares: 20,234.282112 ÷ 10,000 = 2.023428 ha.
- Direct factor: 1 ac = 0.40468564 ha.
Essential Conversion Factors
Acre: US & UK land parcels (43,560 ft²)
ac to ha formula
Direct Answer: 1 ac = 0.40468564 ha, so multiply by 0.40468564: ha = ac × 0.40468564. Going back: ac = ha × 2.4710538.
How to convert acres to hectares
An international acre is exactly 4,046.8564224 m² and a hectare is 10,000 m², so 1 acre = 0.40468564 ha. Multiply acres by 0.4047 to get hectares.
1. ac → ha
Multiply the number of acres by the conversion factor:
Example: 5 ac × 0.40468564 = 2.023 ha.
2. ha → ac
To go back, divide by the same factor, or multiply by its reciprocal, 2.4710538:
Example: 2.023 ha ÷ 0.40468564 = 5 ac.
Mental math: multiply by 0.4
Multiply by 0.4, then add about 1%:
50 acres: 50 × 0.4 = 20, plus 0.2 = 20.2 ha (exact: 20.23 ha).
1 ac in other area units
| Unit | 1 ac equals | Typical use |
|---|---|---|
| Square Millimeter | 4,046,856,400 mm² | Wire cross-sections and electronics |
| Square Centimeter | 40,468,564 cm² | Paper, tiles and small surfaces |
| Square Meter | 4,046.8564 m² | SI unit of area — rooms, apartments and flooring |
| Are | 40.468564 a | Garden plots and small parcels (100 m²) |
| Hectare | 0.40468564 ha | Farmland, forests and land registries (10,000 m²) |
| Square Kilometer | 0.0040468564 km² | Cities, lakes and national territories |
| Square Inch | 6,272,640 in² | Screens, gaskets and small parts |
| Square Foot | 43,560 ft² | US & UK real estate and floor plans |
| Square Yard | 4,840 yd² | Carpet, turf and landscaping (9 ft²) |
| Square Mile | 0.0015625 mi² | Counties, states and large regions (640 acres) |
ac to ha chart
| ac | ha |
|---|---|
| 0.25 | 0.101 |
| 0.5 | 0.202 |
| 0.75 | 0.304 |
| 1 | 0.405 |
| 1.5 | 0.607 |
| 2 | 0.809 |
| 2.5 | 1.012 |
| 3 | 1.214 |
| 4 | 1.619 |
| 5 | 2.023 |
| 6 | 2.428 |
| 8 | 3.237 |
| 10 | 4.047 |
| 15 | 6.07 |
| 20 | 8.094 |
| 25 | 10.117 |
| 30 | 12.141 |
| 40 | 16.187 |
| 50 | 20.234 |
| 75 | 30.351 |
| 80 | 32.375 |
| 100 | 40.469 |
| 160 | 64.75 |
| 200 | 80.937 |
| 320 | 129.499 |
| 500 | 202.343 |
| 640 | 258.999 |
| 1,000 | 404.686 |
ha to ac chart
| ha | ac |
|---|---|
| 0.1 | 0.25 |
| 0.2 | 0.49 |
| 0.25 | 0.62 |
| 0.4 | 0.99 |
| 0.5 | 1.24 |
| 0.75 | 1.85 |
| 1 | 2.47 |
| 1.5 | 3.71 |
| 2 | 4.94 |
| 2.5 | 6.18 |
| 3 | 7.41 |
| 4 | 9.88 |
| 5 | 12.36 |
| 6 | 14.83 |
| 8 | 19.77 |
| 10 | 24.71 |
| 12 | 29.65 |
| 15 | 37.07 |
| 20 | 49.42 |
| 25 | 61.78 |
| 30 | 74.13 |
| 40 | 98.84 |
| 50 | 123.55 |
| 75 | 185.33 |
| 100 | 247.11 |
| 200 | 494.21 |
| 500 | 1,235.53 |
| 1,000 | 2,471.05 |
Frequently Asked Questions
What is 1 ac in ha?
1 ac is 0.405 ha (1 × 0.40468564).
What is 100 ac in ha?
100 ac is 40.469 ha (100 × 0.40468564).
How many hectares is a section of land?
A section is one square mile, 640 acres: 259 hectares. A quarter section (160 acres) is 64.75 ha.
What is an acre in square meters?
One acre is 4,046.86 m². See the acres to square meters page for a full chart.