Convert Acre (acre) to Square kilometer (km²) (km2)
Category: Area
1 acre = 0.004047 km2
High-precision rounding: 6 decimals
How to convert acre to square kilometer (km²)
We convert by pivoting through the SI base unit for Area and applying exact factors where applicable.
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Quick conversion table
Handy values for Acre → Square kilometer (km²). Click a value to open that exact result.
Conversion formula
Linear unit conversions use standardized factors; many are exact by definition (e.g., 1 in = 25.4 mm, 1 ft = 0.3048 m).
Common mistakes
- Squaring a length conversion factor incorrectly or forgetting to square it.
Unit facts
- Acre: An acre is exactly 4,046.8564224 m²; traditional land measure in the Anglosphere.
About Area
Area equals length squared. It appears in real estate, land management, material takeoffs, and GIS. Square meters are SI standard; acres and hectares are common for land reporting in different regions.
About Acre
Acre
Exactly 4,046.8564224 m². Traditional land area in US/UK real estate and agriculture.
History: Medieval origins as the area ploughable in a day; later standardized to a fixed metric value.
About Square kilometer (km²)
Square kilometer (km²) is a commonly used unit within the Area category.
Related conversions from acre
- acre → ha Hectare (ha)
- acre → ft2 Square foot (ft²)
- acre → m2 Square meter (m²)
- acre → yd2 Square yard (yd²)