Acres (ac) to Square kilometers (km²) Conversion
Acres
The acre is a unit of area equal to exactly 4,046.8564224 square metres, the standard unit for land measurement in the United States and United Kingdom. Its origin lies in medieval English agriculture: an acre was the amount of land a yoke of oxen could plough in a single day, standardised as a furlong (220 yards) long and a chain (22 yards) wide — exactly 43,560 square feet. One square mile contains exactly 640 acres.
Square kilometers
The square kilometre is a unit of area equal to one million square metres (10⁶ m²) and is the standard unit for expressing the surface areas of countries, cities, lakes, forests, and other large geographic features. Russia, the world's largest country, covers approximately 17.1 million km². The surface area of Earth is approximately 510.1 million km², of which about 70.8% is ocean.
| Acres (ac) | Square kilometers (km²) |
|---|---|
| 0.1 ac | 0.000405 km² |
| 1 ac | 0.00405 km² |
| 2 ac | 0.00809 km² |
| 3 ac | 0.0121 km² |
| 5 ac | 0.0202 km² |
| 10 ac | 0.0405 km² |
| 20 ac | 0.0809 km² |
| 30 ac | 0.1214 km² |
| 50 ac | 0.2023 km² |
| 100 ac | 0.4047 km² |
| 1000 ac | 4.0469 km² |
Frequently Asked Questions (FAQ)
How many square kilometers are in 1 acres?
1 acres (ac) is exactly 0.004047 square kilometers (km²).
How do I convert acres to square kilometers?
Multiply the value in acres by 0.004047 to get the result in square kilometers. Or use the converter above — type any number and see the result instantly.