Acre ac
About the Acre
The acre is 4840 square yards, one chain by one furlong, exactly 4046.8564224 square metres. It originally represented the land a yoke of oxen could plough in a day. One square mile contains 640 acres, and an acre is about 0.405 hectares.
Related Units
Hectare
ha1 ha = 10,000 m² (exact)
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Barn
b10⁻²⁸ m² (exact)
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Tsubo
坪400/121 m² ≈ 3.306 m²
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Inch
in25.4 mm (exact)
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