Area Unit Converter
Convert area between square metres, square feet, acres, hectares and square miles with exact factors.
How it works
square metres = value × factor(from) · result = m² ÷ factor(to) (1 acre = 4046.8564224 m², 1 ha = 10000 m²)
Area converts through the square metre. Because area scales with length squared, the factors are the length factors squared — one square foot is 0.3048² = 0.09290304 m². An acre is historically 43,560 square feet (a chain by a furlong), while a hectare is a clean 10,000 m², which is why they do not line up neatly (1 ha ≈ 2.471 acres).
Worked example
Convert 1 acre to square feet: 1 × 4046.8564224 = 4046.8564 m², then 4046.8564 ÷ 0.09290304 = 43,560 ft². That is the exact definition of an acre in square feet.
Sources: Acre — Wikipedia
Frequently asked questions
How many square feet are in an acre?
Exactly 43,560 square feet. An acre was originally the area a yoke of oxen could plough in a day — one chain (66 ft) by one furlong (660 ft).
How big is a hectare compared with an acre?
A hectare is 10,000 m², about 2.471 acres. Conversely an acre is about 0.4047 hectares. Hectares are the metric standard for land area worldwide.
Why are area factors the square of length factors?
Because area is length times length. If one foot is 0.3048 m, then one square foot is 0.3048 × 0.3048 = 0.09290304 m² — the length conversion applied twice.
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This calculator is for educational purposes. Double-check important results before acting on them.