Select a category and enter your values below
Multiple conversions
To convert from Are (a) to Square Nanometer (nm2), use the following formula:
Square Nanometer (nm2)
= 100 × 1018× Are (a)
= 1020× Are (a)
To convert from Are (a) to Square Micrometer (μm2), use the following formula:
Square Micrometer (μm2)
= 100 × 1012× Are (a)
= 1014× Are (a)
To convert from Are (a) to Square Millimeter (mm2), use the following formula:
Square Millimeter (mm2)
= 100 × 106× Are (a)
= 108× Are (a)
To convert from Are (a) to Square Centimeter (cm2), use the following formula:
Square Centimeter (cm2)
= 100 × 104× Are (a)
= 106× Are (a)
To convert from Are (a) to Square Decimeter (dm2), use the following formula:
Square Decimeter (dm2)
= 100 × 100× Are (a)
= 104× Are (a)
To convert an area from ares (a) to square meters (m²), multiply by 100.
An are is by definition the area of a 10 m × 10 m square, so the factor is exactly 100. Divide by 100 to go back.
A rural land listing describes a parcel of 4.5 a, and the zoning rules are written in square meters:
The reverse: a 1,200 m² plot is 12 a.
| a | m² |
|---|---|
| 0.5 | 50 |
| 1 | 100 |
| 4.5 | 450 |
| 10 | 1,000 |
| 100 | 10,000 (= 1 ha) |
The are is the odd survivor of metric land measure: everyone knows its multiple, the hectare (100 a), and its submultiple, the centiare (0.01 a = exactly 1 m²), yet the base unit itself has faded from everyday speech. It persists in legal land records: French notarial deeds and cadastral extracts still write parcels as "1 ha 12 a 50 ca" — which is precisely 11,250 m² read off with no arithmetic beyond place value, since the ha/a/ca system is base-100 throughout. Swiss, Dutch, and several Eastern European registries use the same convention, and land in parts of South Asia is sold in ares outright. The conversion matters most when such records meet modern planning documents in m² — building-coverage ratios, minimum plot sizes, tax assessments. One trap: in informal listings the bare word "are" is sometimes locally repurposed for other plot units, so a figure that seems 100× off may be using a regional land measure rather than the metric are. When the document is official, though, ×100 is exact and the ladder is as tidy as metric gets.
To convert from Are (a) to Hectare (ha), use the following formula:
Hectare (ha)
= 100 × 1104× Are (a)
= 1100× Are (a)
= 0.01× Are (a)
To convert from Are (a) to Square Kilometer (km2), use the following formula:
Square Kilometer (km2)
= 100 × 1106× Are (a)
= 1104× Are (a)
= 10-4× Are (a)
To convert from Are (a) to Square Inch (in2), use the following formula:
Square Inch (in2)
= 100 × 10.7639 × 144× Are (a)
= 155000.16× Are (a)
With 10.7639 is the ratio between the base units Square Foot (ft2) and Square Meter (m2).
To convert from Are (a) to Square Yard (yd2), use the following formula:
Square Yard (yd2)
= 100 × 10.7639 × 19× Are (a)
= 119.59888888888888889× Are (a)
With 10.7639 is the ratio between the base units Square Foot (ft2) and Square Meter (m2).
To convert from Are (a) to Square Foot (ft2), use the following formula:
Square Foot (ft2)
= 100 × 10.7639× Are (a)
= 1076.39× Are (a)
With 10.7639 is the ratio between the base units Square Foot (ft2) and Square Meter (m2).
To convert from Are (a) to Acre (ac), use the following formula:
Acre (ac)
= 100 × 10.7639 × 143560× Are (a)
= 0.024710514233241505969× Are (a)
With 10.7639 is the ratio between the base units Square Foot (ft2) and Square Meter (m2).
To convert from Are (a) to Square Mile (mi2), use the following formula:
Square Mile (mi2)
= 100 × 10.7639 × 127878400× Are (a)
= 0.000038610178489439853076× Are (a)
With 10.7639 is the ratio between the base units Square Foot (ft2) and Square Meter (m2).
An are (a) is a metric unit of area, defined as 100 square meters (100 m2).
It is part of the same system as the more widely known hectare. The plural form is ares.
The hectare (ha), a much more common unit for measuring land, is derived directly from the are.
The prefix 'hecto-' means 100, so one hectare is equal to 100 ares.
Since one are is 100 square meters, a hectare is equivalent to 10,000 square meters (100 ares × 100 m2/are). This makes the hectare an ideal unit for measuring large areas, such as farms, forests, and parks.
The are was first established as part of the original French metric system in 1795. It was designed to serve as a standard base unit for measuring land, simplifying calculations required by older, traditional units.
While the hectare is more common today in agriculture and forestry, the are is still used in specific contexts, such as real estate and land registries in many countries, particularly throughout Europe.
The are serves as the foundation for other metric units of land area, making conversions straightforward. The most common related units include: