What Area Converter does
This area converter changes a figure between ten units: square millimetres, square centimetres, square metres, square kilometres, square inches, square feet, square yards, acres, hectares and square miles. The numbers people look up most are fixed: 1 square metre is 10.76391 square feet, 1 acre is 43,560 square feet or 0.404686 hectares, 1 hectare is 2.471054 acres, and 1 square mile is exactly 640 acres. Results are shown to six decimal places, with a Formula line giving the factor for the pair you chose and a table listing your area in every unit. It works from a single area figure, so multiply length by width first if you only have the sides.
Area conversion chart: what one of each unit equals
Each row is the tool's result for a Value of 1 in that unit.
| 1 unit | Square metres | Square feet | Acres | Hectares |
|---|---|---|---|---|
| 1 square inch | 0.000645 | 0.006944 | 1.594225e-7 | 6.451600e-8 |
| 1 square foot | 0.092903 | 1 | 0.000023 | 0.000009 |
| 1 square yard | 0.836127 | 9 | 0.000207 | 0.000084 |
| 1 square metre | 1 | 10.76391 | 0.000247 | 0.0001 |
| 1 acre | 4,046.856422 | 43,560 | 1 | 0.404686 |
| 1 hectare | 10,000 | 107,639.104167 | 2.471054 | 1 |
| 1 square kilometre | 1,000,000 | 10,763,910.41671 | 247.105381 | 100 |
| 1 square mile | 2,589,988.110336 | 27,878,400 | 640 | 258.998811 |
Thousands separators are added here for reading. The Result line shows plain digits, such as 43560 ft², and writes values below 0.000001 in scientific notation.
Square feet to square metres for common home and room sizes
Useful when a listing or floor plan is quoted in the other system.
| Square feet | Square metres | Square metres | Square feet |
|---|---|---|---|
| 100 ft² | 9.290304 m² | 10 m² | 107.639104 ft² |
| 300 ft² | 27.870912 m² | 20 m² | 215.278208 ft² |
| 500 ft² | 46.45152 m² | 50 m² | 538.195521 ft² |
| 850 ft² | 78.967584 m² | 75 m² | 807.293281 ft² |
| 1,000 ft² | 92.90304 m² | 100 m² | 1,076.391042 ft² |
| 1,500 ft² | 139.35456 m² | 150 m² | 1,614.586563 ft² |
| 2,000 ft² | 185.80608 m² | 200 m² | 2,152.782083 ft² |
| 2,500 ft² | 232.2576 m² | 1,000 m² | 10,763.910417 ft² |
The left pair and the right pair are separate conversions placed side by side, not equal areas.
Acres to square feet, square metres and hectares
Common plot and field sizes, from a small building lot to a full square mile.
| Acres | Square feet | Square metres | Hectares |
|---|---|---|---|
| 0.1 | 4,356 | 404.685642 | 0.040469 |
| 0.25 | 10,890 | 1,011.714106 | 0.101171 |
| 0.5 | 21,780 | 2,023.428211 | 0.202343 |
| 1 | 43,560 | 4,046.856422 | 0.404686 |
| 2 | 87,120 | 8,093.712845 | 0.809371 |
| 5 | 217,800 | 20,234.282112 | 2.023428 |
| 10 | 435,600 | 40,468.564224 | 4.046856 |
| 40 | 1,742,400 | 161,874.256896 | 16.187426 |
| 100 | 4,356,000 | 404,685.64224 | 40.468564 |
| 640 | 27,878,400 | 2,589,988.110336 | 258.998811 |
Why area factors are the length factors squared
area in new unit = area × (length factor)²
A foot is 0.3048 metres, so a square foot is 0.3048 × 0.3048 = 0.09290304 square metres. A yard is 3 feet, so a square yard is 9 square feet. A foot is 12 inches, so a square foot is 144 square inches. A kilometre is 1,000 metres, so a square kilometre is 1,000,000 square metres, not 1,000. A common mistake is multiplying square metres by 3.28 instead of 10.764, which understates a floor area by more than two thirds.
Worked area conversions
A flat listed in square feet
Value 850, From Square foot (ft²), To Square metre (m²)
78.967584 m², with the Formula line showing 1 ft² = 0.092903 m²
The Rounded line shows 78.97 m², which is the figure most listings would print.
A room measured in feet
A 20 ft by 15 ft room is 300 square feet. Value 300, From Square foot (ft²), To Square metre (m²)
27.870912 m²
The table underneath also gives 33.333333 yd², handy for carpet priced by the square yard.
A plot in acres to hectares
Value 5, From Acre, To Hectare (ha)
2.023428 ha
The same table row for square metres reads 20234.282112 m².
A lot size in square feet to acres
Value 7500, From Square foot (ft²), To Acre
0.172176 ac
Here the Formula line reads 1 ft² = 0.000023 ac because that factor is cut to six decimals. The Result itself is calculated at full precision.
A large estate in hectares
Value 250, From Hectare (ha), To Acre
617.763454 ac
The same area is 2.5 km², since 100 hectares make one square kilometre.
What an acre and a hectare actually are
An acre is defined as 4,840 square yards. It began as a strip one furlong long and one chain wide, which is 660 feet by 66 feet, and that is where 43,560 square feet comes from. An acre has no fixed shape: a square acre is about 208.7 feet on each side. For scale, an American football field including both end zones is 57,600 square feet, which the tool converts to 1.322314 acres.
A hectare is a metric unit equal to 10,000 square metres, a square 100 metres by 100 metres. One hundred hectares make a square kilometre. Farm and forestry figures in most countries are given in hectares, while property in the United States, and often in the UK, is described in acres.
The tool uses the international acre of 4,046.8564224 square metres. It does not offer the US survey acre, which differs by about 4 parts in a million, or regional land units such as the bigha, gunta, cent, marla, kanal, rai or dunam, whose sizes vary by region.
How to use it
- 1
Enter the area in the Value box, for example 850.
- 2
Choose the unit that figure is in from the From list, such as Square foot (ft²).
- 3
Choose the unit you want from the To list, such as Square metre (m²).
- 4
Read the Result, then check the Formula line under Conversion details for the factor used.
- 5
Use the Same value in every unit table to read the area in any of the other nine units without changing the lists.