Unit-To-Unit Area conversion

Acres to Hectares

1 acre = 0.404685642 hectares

An acre is 0.404686 hectares, so two and a half acres make roughly a hectare. Agricultural subsidies and land registries in Europe work in hectares while transactions are often still discussed in acres.

Formula ha = ac × 0.40468564224

=

Type in either field — the other updates on every keystroke. Need other units? Open the full area converter.

Acres to Hectares — quick reference
AcreHectare
1 ac0.404686 ha
2 ac0.809371 ha
3 ac1.214057 ha
4 ac1.618743 ha
5 ac2.023428 ha
10 ac4.046856 ha
15 ac6.070285 ha
20 ac8.093713 ha
25 ac10.117141 ha
50 ac20.234282 ha
100 ac40.468564 ha
500 ac202.342821 ha
1000 ac404.685642 ha
Hectares to Acres — reverse
HectareAcre
1 ha2.471054 ac
2 ha4.942108 ac
3 ha7.413161 ac
4 ha9.884215 ac
5 ha12.355269 ac
10 ha24.710538 ac
15 ha37.065807 ac
20 ha49.421076 ac
25 ha61.776345 ac
50 ha123.552691 ac
100 ha247.105381 ac
500 ha1235.526907 ac
1000 ha2471.053815 ac

Worked examples

Common values
SituationFromTo
Quarter acre0.25 acres0.1012 ha
One acre1 acre0.4047 ha
Large garden2.5 acres1.012 ha
Small farm10 acres4.047 ha
Farm100 acres40.47 ha
Square mile640 acres259 ha

Mental-math shortcut

Multiply by 0.4, which reads about 1.2% low. 100 acres is about 40 ha, against an exact 40.47.

Where this conversion comes up

Farms and land listings cross between acres and hectares. A 100-acre farm is 40.47 ha.

Common mistakes

A hectare is 10,000 m², about 2.47 acres, so do not simply double an acre figure to get hectares.

Background

The international acre is exactly 4,046.8564224 m², defined through the international yard.

Learn more

Related guides: Imperial vs metric: differences and quick conversion tricks

Frequently asked

How many hectares are in a acre?
1 acre = 0.404685642 hectares. In the other direction, 1 hectare = 2.471053815 acres.
What is a acre?
An acre is 43,560 square feet, or 4,046.8564224 square metres — historically the land one ox team could plough in a day. It is the standard US and UK land unit.
What is a hectare?
A hectare is 10,000 square metres: a square 100 metres on a side. It is the international unit for agricultural and forestry land.
How many hectares is 10 acres?
10 acres is 4.047 hectares.

Related area conversions

Square Feet to Square Metres Square Metres to Square Feet Hectares to Acres Acres to Square Feet Square Miles to Square Kilometres Square Inches to Square Centimetres Square Yards to Square Feet