Convert Acres to Square Kilometers
Convert Acres (ac) to Square Kilometers (km²) instantly and accurately.
Conversion Formula
km² = ac × 0.004046856422
About Acres
An acre is a traditional unit of land area used primarily in the United States, United Kingdom, and countries with British heritage. One acre equals 43,560 ft² or about 4,047 m². Historically based on the area a yoke of oxen could plow in one day, it remains the standard for measuring agricultural land, residential plots, and rural properties. A football field (without end zones) is roughly 1.32 acres, and most suburban house lots range from 0.25 to 1 acre.
About Square Kilometers
A square kilometer (km²) is a metric unit of area equal to a square with sides of one kilometer (1,000 m × 1,000 m). It is used for measuring large land areas such as cities, forests, lakes, and countries. Manhattan (New York) is about 59 km², and Monaco (the second smallest country) is just over 2 km². This unit is essential in geography, urban planning, forestry, and environmental impact studies.
Quick Reference Table
| Acres (ac) | Square Kilometers (km²) |
|---|---|
| 1 ac | 0.00404686 km² |
| 2 ac | 0.00809371 km² |
| 5 ac | 0.0202343 km² |
| 10 ac | 0.0404686 km² |
| 25 ac | 0.101171 km² |
| 50 ac | 0.202343 km² |
| 100 ac | 0.404686 km² |