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.
What is square inch?
A square inch is a unit of area in imperial and US customary systems equal to 1/144 of a square foot. It is used for measuring small surfaces, printed circuit boards, and product specifications in imperial-based industries.
Real-world uses
Square inches are used for pressure measurements (psi = pounds per square inch), display pixel density (pixels per square inch), and small-area calculations for labels, stamps, and PCB layouts in the US. Cooking pan sizes are sometimes described in square inches.
History
The square inch derives from the inch, which was standardized internationally in 1959 as exactly 25.4 mm. It has long been used in American and British engineering for specifying small areas, cross-sections, and pressure measurements.
Common mistakes
Confusing square inches with cubic inches (a volume unit used for engine displacement). Also, forgetting that 1 ft² = 144 in² (12 × 12), not 12 in².
When is this conversion used?
Converting between are and square inch 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 are = 155,000.31000062 square inch
1 square inch = 0.00064516 square metre
How to convert are to square inch
To convert are to square inch, multiply the value by 155,000.31000062.
To convert square inch back to are, multiply by 0.00000645.
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: are to square inch
| are | square inch |
|---|---|
| 0.1 | 15,500.03100006 |
| 0.5 | 77,500.15500031 |
| 1 | 155,000.31000062 |
| 2 | 310,000.62000124 |
| 5 | 775,001.5500031 |
| 10 | 1,550,003.1000062 |
| 25 | 3,875,007.7500155 |
| 50 | 7,750,015.500031 |
| 100 | 15,500,031.000062 |
| 250 | 38,750,077.500155 |
| 500 | 77,500,155.00031 |
| 1,000 | 155,000,310.00062001 |
Common values
| are | square inch | |
|---|---|---|
| A4 paper | 0.00062 are | 96.1001922 square inch |
| Parking space | 0.125 are | 19,375.03875008 square inch |
| Tennis court | 2.6087 are | 404,349.30869862 square inch |
| Football field (soccer) | 71.4 are | 11,067,022.13404427 square inch |
| Central Park, NYC | 34,100 are | 5.285511e+09 square inch |