Squares of length units
Every area unit is the area of a square whose side is a length unit: a square foot is a square one foot on each side, a square meter one meter on each side. Two units have their own names. The acre, 43,560 square feet, comes from the old English measure of land a team of oxen could plow in a day. The hectare, 10,000 square meters, is the metric unit for land, and the are, 100 square meters, is its smaller sibling.
How to use this converter
Type an area in any field and all the other units update instantly. Start with what you have, such as the square footage of a listing, the acreage of a lot or the square meters of a European apartment. Each pair below the converter has its own page with the formula, a worked example and a chart.
Why the factors are squared
When a length converts by a factor k, the area converts by k². A meter is 3.28084 feet, so a square meter is 3.28084² = 10.7639 square feet, not 3.28. The same logic gives 6.4516 cm² per square inch (2.54²) and 2.58999 km² per square mile (1.609344²). Forgetting the square is the most common area conversion mistake.
Handy reference points
- 1 m² ≈ 10.764 ft², and 1 ft² ≈ 0.0929 m²
- 1 yd² = 9 ft² ≈ 0.836 m²
- 1 acre = 43,560 ft² ≈ 4,047 m²
- 1 hectare = 10,000 m² ≈ 2.471 acres
- 1 square mile = 640 acres ≈ 2.59 km²
Measuring a room or a lot
For a rectangle, multiply length by width in the same unit, then convert the result. For an L-shaped room, split it into rectangles and add them up. For flooring or paint, add 5 to 10% for waste and cuts before you buy.
Area units compared
| Unit | Symbol | In square meters |
|---|---|---|
| Square centimeter | cm² | 0.0001 |
| Square meter | m² | 1 |
| Are | a | 100 |
| Hectare | ha | 10,000 |
| Square kilometer | km² | 1,000,000 |
| Square inch | in² | 0.00064516 |
| Square foot | ft² | 0.092903 |
| Square yard | yd² | 0.836127 |
| Acre | ac | 4,046.86 |
| Square mile | mi² | 2,589,988 |
The units in detail
What is a square centimeter?
The square centimeter is the area of a square 1 cm on each side, one ten-thousandth of a square meter. It is used for small surfaces such as labels, photos, skin patches and the cross-section of beams. One square inch is exactly 6.4516 cm².
What is a square meter?
The square meter is the SI unit of area, a square one meter on each side. Outside the US it is the unit of home sizes, rents, flooring and paint coverage. One square meter is about 10.76 square feet.
What is an are?
The are equals 100 square meters, a square 10 m on each side. It is rare in English but still used in land registries in France, Switzerland and elsewhere in Europe, and in India, where a cent is close to 40 square meters.
What is a hectare?
The hectare equals 10,000 square meters, a square 100 m on each side. It is the international unit for farms, forests and land plots. One hectare is about 2.47 acres; a full-size soccer pitch covers about 0.7 hectare.
What is a square kilometer?
The square kilometer equals one million square meters, or 100 hectares. It measures cities, lakes, parks and countries; Manhattan covers about 59 km² of land. One square kilometer is about 0.386 square mile.
What is a square inch?
The square inch is the area of a square one inch on each side, exactly 6.4516 cm². It shows up in tile and screen areas, printing and in pressure units such as pounds per square inch (psi).
What is a square foot?
The square foot is the area of a square one foot on each side, exactly 0.09290304 m². It is the US unit for home sizes, rents, flooring, drywall and paint coverage. Listings often abbreviate it as sq ft or SF.
What is a square yard?
The square yard equals 9 square feet, about 0.836 m². Carpet, sod and some fabrics are priced by the square yard in the United States, and contractors use it for paving and landscaping estimates.
What is an acre?
The acre equals 43,560 square feet, about 4,047 m² or 0.405 hectare. It is the US and UK unit for land, lots and farms. An American football field, end zones included, covers about 1.32 acres.
What is a square mile?
The square mile equals 640 acres, about 2.59 km². It measures the area of US cities, counties and states, and in the public land survey a one-square-mile parcel is called a section.