Area Converter

Type an area, pick the unit you have and the unit you want, and the result updates as you type. The seven units covered — square meters, square feet, square yards, acres, hectares, square kilometers and square miles — handle nearly every area question that comes up in practice, from comparing apartment listings to reading a farm survey. The answer appears to four decimal places, which is finer than any property deed, building plan or field survey needs.

Why area units are such a tangle

Length has one dominant international standard and a few stubborn holdouts. Area inherited all of that and added a second complication of its own. Some units are simply the square of a length: the square meter, square foot and square mile behave exactly the way their underlying length was defined. Others — the acre and the hectare above all — began as land measures in their own right, pinned to how much ground a person or an ox team could work rather than to any tidy multiple of a smaller unit. Converting between those two families is where the uneven numbers come from.

From the metre to the square metre

Every metric area unit descends from the metre, and the metre has been redefined several times since the French Revolution. The National Assembly took up the idea in 1791 and set the metre at one ten-millionth of the distance from the equator to the North Pole along the meridian through Paris. Once surveying expeditions had measured that arc, the standard was cast as a platinum bar in 1799, the Mètre des Archives. A platinum-iridium bar replaced it in 1889, a wavelength of krypton-86 light took over in 1960, and in 1983 the metre was fixed as the distance light travels in a vacuum in 1/299,792,458 of a second — the definition still in force. The square metre is that length squared, so every redefinition tightened the area unit at the same moment.

The metric land units came early. On 7 April 1795, the French law of 18 Germinal, Year III, named the are — 100 square metres — as the unit for land. The hectare, from the prefix hecto- meaning a hundred, is a hundred ares: 10,000 m², a square 100 metres on a side. When the modern SI was organised in 1960 the are was left off the list of accepted units, but the hectare survived on practical grounds and is still the standard measure for land almost everywhere the metric system took hold.

Where the acre and the hectare come from

The acre is the outlier because it was never defined as a square. Medieval usage tied it to labour: the area a team of oxen could plough in a day. In shape it settled as one furlong by one chain — 660 feet by 66 feet. The furlong, or "furrow length," was as far as the team would draw a plough before resting, and the chain is a tenth of that. Multiply the two and you get 43,560 square feet, or 4,840 square yards, the figure written into the British Weights and Measures Act 1878 after centuries of English statutes — under Edward I, Edward III and Henry VIII among others — had pushed the measure toward a single fixed value. In exact metric terms the acre is 4,046.8564224 m². The long, narrow strip was deliberate: it kept the number of times the team had to turn the plough to a minimum.

The hectare is what replaced the acre across most of the world — a clean 100 m by 100 m square. A pitch built to the 105 by 68 m size FIFA recommends covers 7,140 m², so a hectare is about 1.4 of them. One hectare is 2.4711 acres. A square mile holds exactly 640 acres, because a mile is 5,280 feet, a square mile is 27,878,400 ft², and dividing by 43,560 gives 640. That is why US rural land is still described in sections and quarter-sections: a section is a square mile, a survey township holds 36 of them, and the 160-acre claim granted under the Homestead Act of 1862 was a quarter-section.

How the conversion works

Each unit is stored as an exact factor relative to the square metre, and every conversion passes through that base unit:

result = value × factor_from ÷ factor_to

The defaults make a good worked example: 150 square meters into square feet. Since the International Yard and Pound Agreement of 1 July 1959 — signed by the United States, the United Kingdom, Canada, Australia, New Zealand and South Africa — a foot has been exactly 0.3048 m, so a square foot is 0.3048² = 0.09290304 m². Dividing 150 by 0.09290304 gives 1614.5866 ft². Because every imperial length now has an exact metric definition, the squared factors are exact too; nothing here is an approximation, and the calculator carries full precision internally, rounding only for display.

Routing everything through the square metre keeps the arithmetic honest. Any of the seven units converts to any other with one multiplication and one division, and adding a new unit means storing a single extra factor rather than a whole grid of pairings.

Listings read differently by country

Real estate is where area units cause the most confusion. The US and Canada list interiors in square feet; most of Europe, Latin America and Asia use square meters; the UK mixes both, often quoting ft² for flats and acres for gardens and plots. Australia lists homes in m² but rural land in hectares. As reference points, a 1,000 ft² apartment is 92.9 m², and the 2,142 ft² median floor area the Census Bureau recorded for new US single-family houses completed in 2025 works out to 199 m². Farmland flips the same way: a 160-acre quarter-section is 64.75 ha.

Quick mental conversions

The exact factors matter for deeds and contracts, but rough arithmetic covers most day-to-day comparisons. To turn square meters into square feet, multiply by 10.75; the true factor is 10.7639, so the shortcut lands within about 0.13 percent, and a 70 m² flat reads as roughly 753 ft². Going the other way, divide square feet by about 10.76. Acres and hectares are close enough that people often treat them as interchangeable at a glance, but the gap is real: a hectare is roughly two and a half acres, so a 50-hectare farm is about 124 acres, not 125. The square yard sits quietly between the two systems, exactly nine square feet and 0.83612736 m², and it still turns up in carpet, paving and fabric where whole-yard pricing is convenient.

Precision notes

Four decimal places cover everyday use with a wide margin. One edge case is worth knowing: some pre-2023 US land records were surveyed in the US survey foot, set by Congress in 1866 as exactly 1200/3937 of a metre. That is 2 parts per million longer than the international foot, which makes the survey acre 4,046.872 m², about 0.016 m² larger. The two versions ran side by side for decades until NIST and NOAA's National Geodetic Survey deprecated the survey foot, naming 31 December 2022 the last day it should be used and leaving the international foot as the sole standard. This converter uses the international definitions throughout.

Frequently asked questions

How many square feet are in a square meter?

One square meter is 10.7639 square feet. A fast mental version is to multiply by 10.75, which lands within 0.13 percent — close enough to know that a 70 m² flat is roughly 753 ft². Going the other way, divide square feet by 10.764.

Is an acre bigger than a hectare?

No, the hectare is the larger unit. One hectare is 10,000 m² while an acre is 4,046.86 m², so a hectare holds 2.4711 acres. A useful visual: a hectare is a 100 m square, about 1.4 times the playing area of a typical soccer pitch.

Why is an acre 43,560 square feet?

Because it started as a furlong by a chain: 660 feet long by 66 feet wide, the strip a team of oxen was expected to plow in a day. Multiplying 660 by 66 gives 43,560 ft². The long, narrow shape kept the number of plow turns to a minimum.

How many acres are in a square mile?

Exactly 640. A mile is 5,280 feet, so a square mile is 27,878,400 ft², and dividing by 43,560 gives 640 acres. The US Public Land Survey System calls this a section, and the classic 160-acre homestead was a quarter-section.

Do other countries use square feet for apartments?

The US and Canada do, and so do Hong Kong, India and Singapore for residential listings. Most of Europe, Latin America, China and Japan quote square meters, and Japan also uses the tsubo, about 3.306 m². The UK sits in between, with newer listings increasingly showing both.