What is square foot?
A square foot is a unit of area in imperial and US customary systems equal to 144 square inches. It is commonly used in the United States for real estate listings, floor plans, and building layouts.
Real-world uses
Square feet are the primary unit for real estate in the United States, Canada, and parts of South Asia. Office space, apartment listings, and retail floor plans are quoted in sq ft. Flooring, tiles, and paint coverage are sold per square foot in these markets.
History
The square foot derives directly from the foot, which has been used since ancient times. It became the de facto real estate standard in the United States and remains deeply entrenched in American property markets despite the global shift toward metric units.
Common mistakes
Forgetting that square footage is an area measure, not a length. A 1,000 sq ft apartment is not 1,000 feet long. Also, nominal tile sizes often include grout spacing, so actual coverage per tile is slightly less than the stated size.
What is square metre?
The square metre is the SI unit of area. It is widely used in real estate, construction, interior design, and land measurement across countries that use the metric system.
Real-world uses
Square metres are the global standard for floor space in real estate listings, construction blueprints, and land surveys outside the US. Solar panel output is rated per square metre, and rental prices in most countries are quoted per m².
History
The square metre is a derived SI unit that follows naturally from the metre. It became the standard area unit as the metric system spread globally. Real estate markets worldwide adopted it as metrication displaced local units like the tsubo (Japan) and pyeong (Korea).
Common mistakes
Confusing linear metres with square metres—a room that is 3 m × 4 m is 12 m², not 7 m. Also, forgetting that when scaling dimensions by a factor, area scales by the square of that factor.
When is this conversion used?
Converting between square foot and square metre is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region.
Worked examples
1 square foot = 0.09290304 square metre
1 square metre = 1 square metre
How to convert square foot to square metre
To convert square foot to square metre, multiply the value by 0.09290304.
To convert square metre back to square foot, multiply by 10.76391042.
Measurement standards
The square metre is the SI derived unit of area. The hectare (10,000 m²) is accepted for use with the SI by the BIPM, particularly for land measurement, though it is not an SI unit itself.
Did you know?
Vatican City, the world's smallest independent state, covers just 0.44 km² (about 109 acres) — smaller than many golf courses. By contrast, Russia spans over 17.1 million km², nearly 39 million times larger.
Quick reference: square foot to square metre
| square foot | square metre |
|---|---|
| 0.1 | 0.0092903 |
| 0.5 | 0.04645152 |
| 1 | 0.09290304 |
| 2 | 0.18580608 |
| 5 | 0.4645152 |
| 10 | 0.9290304 |
| 25 | 2.322576 |
| 50 | 4.645152 |
| 100 | 9.290304 |
| 250 | 23.22576 |
| 500 | 46.45152 |
| 1,000 | 92.90304 |
Common values
| square foot | square metre | |
|---|---|---|
| A4 paper | 0.66736245 square foot | 0.062 square metre |
| Parking space | 134.54888021 square foot | 12.5 square metre |
| Tennis court | 2,807.98131041 square foot | 260.87 square metre |
| Football field (soccer) | 76,854.32037531 square foot | 7,140 square metre |
| Central Park, NYC | 36,704,934.52098015 square foot | 3,410,000 square metre |