Convert Acres to Hectares
Acres to hectares is the conversion you need whenever land is measured in acres but the rest of the world around you works in hectares. One acre is exactly 0.40468564224 hectares — a little under half a hectare — so the number gets smaller when you switch from acres to hectares.
Acres to Hectares conversion table
| Acres (ac) | Hectares (ha) |
|---|---|
| 1 | 0.404686 |
| 2 | 0.809371 |
| 3 | 1.214057 |
| 5 | 2.023428 |
| 10 | 4.046856 |
| 20 | 8.093713 |
| 50 | 20.234282 |
| 100 | 40.468564 |
| 500 | 202.342821 |
| 1,000 | 404.685642 |
The formula
To convert acres to hectares, multiply the number of acres by 0.40468564224:
hectares = acres × 0.40468564224
A worked example
Say you're looking at a 10-acre parcel and want it in hectares:
10 × 0.40468564224 = 4.0468564224 hectares
So 10 acres is just over 4 hectares.
Why the number is exact
A hectare is defined as exactly 10,000 square meters, and an acre is exactly 4046.8564224 square meters — a figure that itself comes from the exact definition of the foot. Divide one by the other and you get exactly 0.40468564224 hectares per acre. Because every step is exact, the conversion is too.
When you'll use it
Comparing farm or land sizes between the US and countries that use hectares, filling in agricultural or planning paperwork, and reading international property listings where hectares are the norm.
Frequently asked questions
How many hectares are in an acre?
Exactly 0.40468564224 hectares. It's an exact figure, not a rounded one, because the acre is defined against the international foot and a hectare is just 10,000 square meters.
Is an acre about half a hectare?
Close — an acre is a little under half a hectare, about 0.405 ha. So if you double a number of acres you get a rough hectare figure, but for anything that matters use the exact factor above.
Is the acres to hectares conversion exact?
Yes. A hectare is exactly 10,000 square meters, and an acre is exactly 4046.8564224 square meters, so an acre works out to exactly 0.40468564224 hectares.