Acres, hectares, square feet and local land units explained
Convert land and floor areas between acres, hectares, square metres and square feet, picture how big each one is, and handle local units such as ropani and cent.
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Tools for this job: Area Converter · Length Converter · Paint and Wallpaper Calculator
Property listings, land records and planning documents use a confusing mix of units: square feet for flats, square metres for floor plans, acres or hectares for land, and local units in many countries. All of them are exact multiples of each other.
The main units
| Unit | In square metres |
|---|---|
| Square foot | 0.0929 |
| Square yard | 0.8361 |
| Acre | 4,046.86 |
| Hectare | 10,000 |
| Square kilometre | 1,000,000 (100 hectares) |
A square metre is about 10.76 square feet. A hectare is about 2.471 acres, and an acre about 0.405 hectares. The Area Converter converts between all of them exactly.
Picturing the sizes
- A hectare is a square 100 metres on each side.
- A full-size football pitch of 105 × 68 metres is about 0.71 hectares, or 1.76 acres.
- An acre is 43,560 square feet — historically, the area a team of oxen could plough in a day.
Why a square metre is not 3.28 square feet
A metre is about 3.28 feet, but area has two dimensions. A square metre is 3.28 feet by 3.28 feet, which is about 10.76 square feet. Using the length factor for an area is the most common conversion mistake, and it makes a property look about three times smaller or larger than it is.
Working out an area
For a rectangle, multiply length by width in the same unit. A plot of 30 × 40 feet is 1,200 square feet, or about 111.5 square metres. Split an irregular shape into rectangles and add them up. Convert lengths first with the Length Converter if your measurements are in mixed units.
Local land units
Many countries still use traditional units in land records. A few examples, with commonly used values:
- Cent (used in parts of South India): one hundredth of an acre, 435.6 square feet.
- Gaj (South Asia): a square yard, 9 square feet.
- Ropani (Nepal, hill regions): about 508.72 square metres, divided into 16 aana of about 31.80 square metres.
- Bigha (Nepal, Terai): about 6,772.63 square metres, divided into 20 kattha of about 338.63 square metres.
Units with the same name can have different sizes in different regions — the bigha varies widely across India, for example. For anything legal, such as a purchase or a land record, confirm the conversion your local land office uses.
Floor area is not always the same thing
A listing's “area” may be carpet area (inside the walls), built-up area (including walls) or a super built-up figure that adds a share of common areas. They can differ by a quarter or more for the same flat, so check which one a price per square foot is based on before comparing.
Rooms and decorating
For a room, floor area decides flooring and carpet; wall area decides paint and wallpaper. The Paint and Wallpaper Calculator works out wall area from a room's dimensions.