Ans

Unit converter

Hectares to acres.

Convert ha to ac and ac to ha. Type in either box and the other follows. A hectare is 2.471 acres, or about two and a half football pitches.

ha → acExact definition
—
Hectares to acres — common values, to 6 significant figures.
haac
0.25 ha0.617763 ac
0.5 ha1.23553 ac
1 ha2.47105 ac
2 ha4.94211 ac
3 ha7.41316 ac
5 ha12.3553 ac
10 ha24.7105 ac
20 ha49.4211 ac
50 ha123.553 ac
100 ha247.105 ac
1 ha=2.471053815 ac 1 ac=0.4046856422 ha

Definitions

  • The hectare is 10 000 m² — a square 100 m on a side, and the metric unit of land area.
  • The acre is 4046.856 4224 m², historically the area one ox team could plough in a day. There are 640 acres in a square mile.
  • This conversion is exact by definition. 1 ha = 2.471053815 ac.
  • Area is converted through m².

How it works

One direction multiplies and the other divides by the same number, so nothing is lost by going back and forth.

The value passes through m², the unit every other area unit on the site is defined against, rather than a number written into this page on its own. That is why the figure here, the figure in the table above and the general area converter always agree.

Display precision limits significant figures rather than decimal places, because one fixed number of decimals is useless across a range this wide. Very large and very small results switch to scientific notation with a proper superscript exponent. The editable box always holds a plain number at full working precision, so you can carry on from either side.

Common questions this answers: how many acres in a hectare (2.47105), how many hectares in an acre (0.404686), and what 5 ha is in acres (12.3553 ac).

From the maker of Ans — a scientific calculator you can own. Same idea: a proper instrument, nothing in the way.