This converts an area value you already know — distinct from the area calculator, which works one out from a shape’s dimensions. Every factor here is exact, derived by squaring the same exact length definitions used elsewhere on this site.
How it works
Squaring an exact length gives an exact area
1 ft² = 0.3048² = 0.09290304 m² exact
1 acre = 4840 yd² = 4046.8564224 m² exact
An acre is legally defined as exactly 4840 square yards, and a hectare is an SI-accepted unit defined as exactly 10,000 m² — neither is a rounded approximation.
How to use this calculator
- Type an area into any field.
- The rest update — square metres, square feet, hectares and acres up front; square kilometres, centimetres, yards and miles behind “More units”.
Frequently asked questions
How big is an acre, really?
4046.86 square metres, or about three-quarters of a football pitch. It is defined as exactly 4840 square yards — a unit that survived from historical land measurement and is still standard for real estate in the US.
Is a hectare exactly 10,000 square metres?
Yes, exactly — a hectare is defined that way, which makes it one of the easiest area conversions on this page: multiply hectares by 10,000 to get square metres, with no rounding involved.
Why does doubling every side of a shape more than double its area?
Because area is built from two linear dimensions multiplied together — doubling each one multiplies the area by four, not two. This converter handles the units; the area vs. volume scaling article on this site’s blog explains why the scaling itself behaves this way.
Are these conversions exact or rounded?
Exact, throughout. Every factor is derived from internationally fixed length definitions rather than a separately-rounded area constant.
