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 are?
An are is a metric unit of area equal to 100 square metres. While largely replaced by the hectare for most practical uses, it is still referenced in some European countries for measuring agricultural plots.
Real-world uses
The are (100 m²) is used in some European countries for small land parcels and garden plots. In France, small agricultural plots and building lots may be listed in ares. It is most commonly encountered as the basis for the hectare (100 ares).
History
The are was defined in 1795 during the creation of the metric system in France as 100 square metres. Though the hectare eclipsed it in common usage, the are remains a legally recognized metric unit in several European countries.
Common mistakes
Confusing the are (a unit of area equal to 100 m²) with the word "are" (verb). Also, many people are unfamiliar with this unit and do not realize that 1 hectare = 100 ares.
When is this conversion used?
Converting between square foot and are 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 = 0.00092903 are
1 are = 100 square metre
How to convert square foot to are
To convert square foot to are, multiply the value by 0.00092903.
To convert are back to square foot, multiply by 1,076.39104167.
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 are
| square foot | are |
|---|---|
| 0.1 | 0.0000929 |
| 0.5 | 0.00046452 |
| 1 | 0.00092903 |
| 2 | 0.00185806 |
| 5 | 0.00464515 |
| 10 | 0.0092903 |
| 25 | 0.02322576 |
| 50 | 0.04645152 |
| 100 | 0.09290304 |
| 250 | 0.2322576 |
| 500 | 0.4645152 |
| 1,000 | 0.9290304 |
Common values
| square foot | are | |
|---|---|---|
| A4 paper | 0.66736245 square foot | 0.00062 are |
| Parking space | 134.54888021 square foot | 0.125 are |
| Tennis court | 2,807.98131041 square foot | 2.6087 are |
| Football field (soccer) | 76,854.32037531 square foot | 71.4 are |
| Central Park, NYC | 36,704,934.52098015 square foot | 34,100 are |