How many hectares are in a acre?

1 ac = 0.404686 ha. To convert any amount, multiply by 0.404686.

How do you convert acres to hectares?

Multiply the number of acres by 0.404686 to get hectares. The formula is shown in the "How it's calculated" section above.

Where does the conversion factor come from?

It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.

Unit converter — Area

Acres to hectares converter

Convert acres (ac) to hectares (ha). Source-cited conversion factor, exact to the displayed precision.

Results are mathematically exact for the displayed precision. How we calculate.

How it's calculated

Convert acres to hectares— the formula

Acres convert to hectares by multiplying by the published conversion factor. The factor below is exact to the precision shown, sourced from the citation under the formula.

ha = ac × 0.404686

ac = ha × 2.4711

Derived from the length conversion factors. 1 acre = 4046.8564224 m² (international acre, 43560 ft²).

Questions

Frequently asked questions

How many hectares are in a acre?
1 ac = 0.404686 ha. To convert any amount, multiply by 0.404686.
How do you convert acres to hectares?
Multiply the number of acres by 0.404686 to get hectares. The formula is shown in the "How it's calculated" section above.
Where does the conversion factor come from?
It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.