Square Meters to Ares (m² to a)

1 square meter equals 0.01 ares exactly.

1 square meter = 0.01 ares

How to convert square meters to ares

To convert square meters to ares, multiply the number of square meters by 0.01. This factor is exact. To go the other way, multiply ares by 100.

ares = square meters × 0.01

Example: 10 square meters = 0.1 ares.

About these units

Square Meter (m²)

Metric (SI)Current unit

The SI unit of area: a square one meter on each side. Used for floor areas and property sizes in most of the world.

Squaring the meter was built into the metric system from the start. The French law of 18 Germinal, Year III (7 April 1795) defined the are, the land unit that gave the hectare its name, as exactly 100 square meters, so the square meter was already the foundation of metric land measure. Nobody is credited with inventing it as a separate unit. It is simply the area of a square one meter on each side, and any SI prefix that works for the meter works for it, with the prefix squared along with the unit.

That squaring catches people out: a square kilometer is one million square meters, not one thousand. Since 1983 the meter has been defined through the speed of light, so the square meter is tied to a constant of nature as well as to the second. A hectare, about the area of Trafalgar Square in London, is 10,000 square meters. In everyday terms one square meter is about 10.76 square feet. Unicode has a compatibility character for it, but the recommended way to write it is the plain superscript two: m².

The square meter is the reference unit for area on this site.

Sources: Wikipedia: Square metre; Wikipedia: Are (unit); NIST: the meter and the SI redefinition

Are (a)

Metric (SI)Traditional unit (still used in some regions)

100 square meters, a square 10 m on a side. Mostly replaced by the hectare (100 ares).

Latin area, meaning an open piece of ground, gave French the word are, the base land unit of the metric system. A French law of 1795 defined it as 100 square meters, a square ten meters on each side, and the hectare was then built as 100 ares, which is why that familiar unit carries the "hecto-" prefix.

The are itself never made it into the modern SI when the system was rationalised in 1960, and the hectare took over for fields, forests and planning. The are survives mostly as a convenience for small plots such as building lots and gardens, and in everyday talk in parts of continental Europe. NIST lists it as exactly 100 square meters, so the figure used here is firm, and 100 ares make one hectare. The hectare is about 2.47 acres, so an are is roughly a fortieth of an acre.

1 are = 100 square meters (exactly).

Sources: Wikipedia: Hectare; NIST SP 811, Appendix B.8 conversion factors

Related conversions

See all area units.