How to convert acres to square kilometers
To convert acres to square kilometers, multiply by 0.0040468564224. Area conversions are essential for real estate, flooring, land surveys, farming and map reading.
Acre to Square Kilometer conversion table
| Acre (ac) | Square Kilometer (km²) |
|---|---|
| 0.1 ac | 0.00040468564224 km² |
| 0.5 ac | 0.0020234282112 km² |
| 1 ac | 0.0040468564224 km² |
| 2 ac | 0.0080937128448 km² |
| 3 ac | 0.0121405692672 km² |
| 4 ac | 0.0161874256896 km² |
| 5 ac | 0.020234282112 km² |
| 10 ac | 0.040468564224 km² |
| 20 ac | 0.080937128448 km² |
| 25 ac | 0.10117141056 km² |
| 50 ac | 0.20234282112 km² |
| 100 ac | 0.40468564224 km² |
| 500 ac | 2.0234282112 km² |
| 1,000 ac | 4.0468564224 km² |
About the units
Acre (ac)
An acre equals 43,560 square feet (4,046.8564224 m²) and is used for land in the US and UK.
Square Kilometer (km²)
A square kilometer equals 1,000,000 m² and measures cities, lakes and countries.
How to use this converter
- Type the number of acres (ac) in the input box.
- The result in square kilometers appears instantly — no button needed.
- See the same value in every other area unit just below.
- Use “Swap units” to convert square kilometers back to acres.
Tips for better results
- Double-check which system a unit belongs to (for example US vs UK gallons).
- Use the swap button to convert in the opposite direction instantly.
- Bookmark the conversions you use most — each pair has its own page.
Frequently asked questions
How many square kilometers are in one acre?
One acre equals 0.0040468564224 square kilometers. 0.0040468564224 is the exact factor used by this converter.
How do I convert acres to square kilometers?
Multiply the value in acres by 0.0040468564224. To go the other way, multiply square kilometers by 247.105381467.
What is 10 ac in km²?
10 ac = 0.040468564224 km². Also, 5 ac = 0.020234282112 km² and 100 ac = 0.40468564224 km².
What is the difference between a acre and a square kilometer?
An acre equals 43,560 square feet (4,046.8564224 m²) and is used for land in the US and UK. A square kilometer equals 1,000,000 m² and measures cities, lakes and countries.
Is this tool free and private?
Yes — the Acre to Square Kilometer is completely free with no sign-up, and it runs entirely in your browser, so the values you enter are never uploaded to our servers.
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