Acres to Hectares Converter
Convert Acres (ac) to Hectares (ha) instantly, or use the conversion table below to look up common values.
Acres to Hectares conversion table
| Acres (ac) | Hectares (ha) |
|---|---|
| 1 | 0.404686 |
| 2 | 0.809371 |
| 3 | 1.214057 |
| 4 | 1.618743 |
| 5 | 2.023428 |
| 10 | 4.046856 |
| 25 | 10.117141 |
| 50 | 20.234282 |
| 100 | 40.468564 |
How to convert Acres to Hectares
1 ac equals 0.404686 ha. Use the converter above for any value, or read the table for common conversions.
ha = ac × 0.40468564224000003 · ac = ha × 2.471053814671653Multiply a acres figure by 0.404686 to get hectares, or divide it by 2.471054 to go the other way.
Worked examples
- 1 ac= 0.404686 ha
- 5 ac= 2.023428 ha
- 10 ac= 4.046856 ha
- 25 ac= 10.117141 ha
- 100 ac= 40.468564 ha
What these units are
Acres (ac). An acre is 4,046.8564224 square meters, about 0.4047 hectares. It is the traditional land unit of the UK and US and is still used for land in parts of East Africa.
Hectares (ha). A hectare is 10,000 square meters, or 0.01 square kilometers. It is the standard unit for farmland and land-title areas in Tanzania and most metric countries.
Every factor is an exact definition, so the only loss is display rounding. Land figures quoted in acres and hectares are usually rounded at the source.
Converting Acres to Hectares in practice
Working in acres
An acre is exactly 4,046.8564224 square meters, an area of 4,840 square yards, or one chain by one furlong. It is a unit of area, not of length.
Land titles, farm sizes, plots and ranches are described in acres in the United States, the United Kingdom and parts of the Commonwealth. Estate agents quote plot sizes in acres.
One acre equals 0.40468564224 hectares exactly, and a square mile holds exactly 640 acres. The site rounds displayed output, so a figure converted to hectares and back may return one digit away.
The classic mistake is treating an acre as a square of fixed side length; it is any shape with that area, and an acre is roughly 209 feet square only when square. Quoting acres from a deed written in hectares also invites error.
Acres and hectares both describe land, with one acre under half a hectare. A plot stated in hectares is about 2.47 times the same number of acres, so quoting the wrong unit makes land look far larger or smaller.
Reading the result in hectares
A hectare is exactly 10,000 square meters, the area of a square 100 meters on a side, and it equals 0.01 square kilometers. It is the metric unit of land area.
Farmland, forest, parks and large plots are measured in hectares across most of the world, and land registries in metric countries record titles in hectares. Sports fields and golf courses also appear in hectares.
Because a hectare is defined as exactly 10,000 square meters, conversions to acres use the exact acre value of 4,046.8564224 square meters. Display rounding means a hectare to acre conversion and back can differ in the last digit.
The error is treating the hectare as a length measure: a hectare is not 100 meters, it is the area of a square with 100-meter sides, which is 10,000 square meters. Guessing the acre equivalent misstates the plot.
Hectares and acres are the two land units a buyer meets, and hectares and square meters divide the same metric scale. Small urban plots are usually stated in square meters, farmland in hectares, and a figure switched between the two changes by ten thousand.
Checking a acres to hectares conversion
Area factors are the square of the corresponding length factors, so the numbers move much faster than a reader expects. A square meter contains 10,000 square centimeters, and a square kilometer a million square meters, not a thousand.
The units that share a name across systems are still different sizes: a square mile and a square kilometer differ by a factor of about 2.59, and an acre is a fixed area rather than a square with equal sides, so it does not convert like the length units it is named after.
Land is where the reciprocal matters most, because acres and hectares are both in use for the same plots. When a figure moves between them, check it against a shape you can picture — a hectare is a square 100 meters on each side — rather than against the number alone.
Tanzania reference points
Real quantities, converted into the units on this page.
The total surface area of Tanzania, including Zanzibar
947,303 km² = 234,083,669.17999 ac = 94,730,300 ha
Source: UN Statistics Division — World Statistics Pocketbook, country profile: Tanzania · verified 2026-09-14
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