AREA CONVERSION
Acre to Square kilometer.
Convert acre (ac) to square kilometer (km²), with the math explained.
1 ac = 0.004046856422 km²
THE MATH, MADE SIMPLE
How to convert acre to square kilometer
Multiply your acre value by 0.0040468564224 to get the equivalent in square kilometer. Both units are normalized through the square meter.
km² = ac × 0.00404685642210 ac = 0.040468564224 km²
Result rounded to 12 significant digits. Change the precision in the calculator to suit your task.QUICK REFERENCE
ac to km² conversion table
| Acre (ac) | Square kilometer (km²) |
|---|---|
| 1 ac | 0.0040468564224 km² |
| 2 ac | 0.0080937128448 km² |
| 5 ac | 0.020234282112 km² |
| 10 ac | 0.040468564224 km² |
| 20 ac | 0.080937128448 km² |
| 50 ac | 0.20234282112 km² |
| 100 ac | 0.40468564224 km² |
| 500 ac | 2.0234282112 km² |
| 1,000 ac | 4.0468564224 km² |
About the acre
The acre (ac) is a unit of area. One acre equals 4,046.8564224 square meter (base unit) in this calculator.
All acre conversionsAbout the square kilometer
The square kilometer (km²) is a unit of area. One square kilometer equals 1,000,000 square meter (base unit) in this calculator.
All square kilometer conversionsCommon questions
What is 1 ac in km²?
One acre equals 0.0040468564224 km². Use the formula above for other values.
Why might another calculator show a different last digit?
Calculators may round at different stages or use different unit conventions. We keep full JavaScript numeric precision during calculation and round only for display. Choose up to 15 significant digits. Check US versus UK units and the notes for this category.
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