Area units: metric, imperial and historical
m², are, hectare, acre and square foot at a glance
The SI base unit of area is the square meter (m²). It derives from the base measurement of the meter (length² = area) and is the most commonly used area unit in Germany and Europe – for living space, land parcels and technical plans. In construction, the square meter plays a central role: energy performance certificates state the heat transfer coefficient in W/(m²·K), and rents are calculated as a price per m².
In agriculture and the land market, the are (a) and hectare (ha) are common in German-speaking countries. 1 are = 100 m² (a square with 10 m sides), 1 hectare = 100 ares = 10,000 m². An average farm in Germany cultivates around 60–70 hectares. The term "hectare" derives from the Greek words "hekaton" (hundred) and "are". Forest land, nature reserves and farmland are almost exclusively given in hectares.
In the English-speaking world, square feet (ft²) dominate for living space, and the acre for land and agriculture. In the US real estate market, living space is given exclusively in ft²; a house with 2,000 ft² has about 186 m². The acre (about 4,047 m²) is the US standard unit for land area. Historically, the acre goes back to the area a team of oxen could plow in one day – which explains its non-round metric equivalent.
In international real estate purchases, correct area conversion is crucial: buying a vacation home in Florida listed as "0.5 acres" gets you about 2,023 m² of land. A vacation apartment in New York with "800 sq ft" of living space is about 74 m². Land purchases in the United Kingdom also use the acre, which is why conversion matters for British property listings too.
Common sources of error in area conversions: square feet (ft²) and square inches (in²) are sometimes confused – 1 ft² = 144 in². Likewise, the factor-100 difference between are (100 m²) and hectare (10,000 m²) should be kept in mind. When planning garden projects in Germany, the are is the practical unit: an allotment garden of 400 m² equals 4 ares, and a plot of 800 m² equals 8 ares. Our converter supports all common units and displays results clearly with sufficient decimal precision.