Acres to Hectares Converter
Enter any acreage to get the exact equivalent in hectares. The converter also works in reverse: type in hectares to get acres back. You get a comparison against familiar land sizes, a show-your-work panel, and a reference table covering common conversions from a quarter-acre residential lot to 1,000-acre farm tracts.
What is an acre?
An acre is a unit of area used primarily in the United States, the United Kingdom, Canada, and Australia. One acre equals exactly 43,560 square feet or about 4,047 square meters. Historically, it was defined as the amount of land a yoke of oxen could plow in one day, an area approximately 66 feet wide and 660 feet long (one chain by one furlong). Today the international acre is fixed by definition: 1 ac = 4,046.8564224 m², a value standardized by the international yard and pound agreement of 1959. In the US, the slightly different US survey acre (4,046.872 m²) is still used in some federal land descriptions, but the difference is less than 0.001% and is negligible for most purposes.
What is a hectare?
A hectare is the standard metric unit for large land areas, defined as exactly 10,000 square meters (a 100 m x 100 m square). It is part of the International System of Units (SI) and is the unit used by the Food and Agriculture Organization of the United Nations, most national land registries outside the US, and international agriculture reporting. One hectare equals about 2.471 acres. Globally, crop yields, deforestation rates, and land allocation figures are almost always quoted in hectares, making conversion essential for anyone comparing data across countries.
The acres-to-hectares conversion formula
The exact conversion is 1 international acre = 0.40468564224 hectares. To convert acres to hectares, multiply by this factor. To convert hectares to acres, divide by 0.40468564224 (equivalently, multiply by 2.47105381). Example: 10 acres = 10 x 0.40468564224 = 4.0468564224 ha. For a reverse check: 4.0469 ha / 0.40468564224 = 10.000 ac. The factor 1/2.47105381 is the exact reciprocal, so either approach is lossless to full floating-point precision.
Acres vs hectares in real estate and agriculture
In the United States and parts of the UK, residential and agricultural land is almost always advertised in acres. The rest of the world, including the European Union, most of Asia, Africa and South America, uses hectares for both agricultural statistics and real estate. A farm described as 100 acres in the US is about 40.5 hectares, a figure that would appear in an EU subsidy application or a UN food report. Knowing both units, and converting reliably, matters for international real estate transactions, cross-border agricultural data, environmental impact studies, and any project that references land in both metric and non-metric countries.
Acres to Hectares: Common Reference Values
| Acres (ac) | Hectares (ha) | Square meters (m²) | Common context |
|---|---|---|---|
| 0.25 | 0.1012 | 1,012 | Typical US suburban lot |
| 0.5 | 0.2023 | 2,023 | Half-acre residential plot |
| 1 | 0.4047 | 4,047 | One acre (reference) |
| 2 | 0.8094 | 8,094 | Small hobby farm plot |
| 5 | 2.0234 | 20,234 | Small smallholding |
| 10 | 4.0469 | 40,469 | Small market garden |
| 25 | 10.117 | 101,172 | Medium farm parcel |
| 50 | 20.234 | 202,343 | Typical US family farm unit |
| 100 | 40.469 | 404,686 | Large farm tract |
| 200 | 80.937 | 809,371 | Small estate or ranch |
| 640 | 259.00 | 2,589,988 | 1 square mile (1 US section) |
| 1,000 | 404.69 | 4,046,856 | Very large agricultural property |
Conversions for land sizes commonly encountered in real estate, agriculture, and land management. 1 ac = 0.40468564224 ha (NIST exact).
Frequently asked questions
How many hectares are in one acre?
Exactly 0.40468564224 hectares. This is defined from the international agreement on the yard, which fixes 1 yard = 0.9144 m exactly. From there, 1 acre = 4,840 yd² = 4,840 x 0.9144² m² = 4,046.8564224 m² = 0.40468564224 ha.
How many acres are in one hectare?
1 hectare = 10,000 m² = 10,000 / 4,046.8564224 acres = approximately 2.471053814 acres. For quick mental math, 1 ha is roughly 2.5 acres.
What is the difference between an acre and a hectare?
An acre is an imperial unit equal to 4,047 m², while a hectare is a metric unit equal to 10,000 m². A hectare is therefore about 2.47 times larger than an acre. Acres are used mainly in the US, UK, Canada and Australia; hectares are the standard almost everywhere else.
Is there more than one kind of acre?
Yes. The international acre (the standard) is exactly 4,046.8564224 m². The US survey acre (used in some older US federal land descriptions) is about 4,046.87261 m², roughly 0.016 m² or 0.0004% larger. For everyday conversions the difference is irrelevant. This calculator uses the international acre.
How do I convert acres to square meters?
Multiply the number of acres by 4,046.8564224. For example, 5 acres = 5 x 4,046.8564224 = 20,234.282 m². This calculator shows the square-meter equivalent alongside the hectare result.
How large is 1 acre in practical terms?
One acre is about 90% of a US football field (including end zones), roughly 208.7 feet (63.6 m) on a side if it were square, and about the size of 16 standard US tennis courts. It is also approximately the area of a typical suburban block of houses.
Why does the US use acres while most countries use hectares?
The United States, the United Kingdom (for historical property records), and some Commonwealth nations retained imperial units including acres after the 18th and 19th centuries when land surveys were conducted using those standards. Most of the world adopted the metric system during the 19th and 20th centuries, along with the hectare. Changing well-established legal and property records is slow, so acres remain common in US real estate even though the metric system is official in science and international trade.