Convert acres to square kilometers
1 ac = 0.0040468564224 km² — exactly. Both units are defined against the SI, so this factor is a fraction, not an approximation.
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Show this value in all 25 area units
- Square kilometers km² 0.004 046 856 422 4
- Square hectometers hm² 0.404 685 642 24
- Square decameters dam² 40.468 564 224
- Square meters m² 4046.856 422 4
- Square decimeters dm² 404 685.642 24
- Square centimeters cm² 40 468 564.224
- Square millimeters mm² 4 046 856 422.4
- Square micrometers µm² 4 046 856 422 400 000
- Square nanometers nm² 4.0468564224e+21
- Hectares ha 0.404 685 642 24
- Ares a 40.468 564 224
- Decares daa 4.046 856 422 4
- Square inches in² 6 272 640
- Square feet ft² 43 560
- Square yards yd² 4840
- Square miles mi² 0.001 562 5
- Acres ac 1
- Roods ro 4
- Square rods rd² 160
- Sections section 0.001 562 5
- Townships twp 0.000 043 402 777 777 8
- Roofing squares sq 435.6
- Circular mils cmil 7 986 573 297 890
- Barns b 4.0468564224e+31
- Tsubos 坪 1224.174 067 78
Every row is Acre (ac) converted through the square meter, in exact rational arithmetic.
How to convert acres to square kilometers
Multiply the number of acres by 0.0040468564224 to get square kilometers.
The exact factor is 0.0040468564224 — as a fraction, 158080329/39062500000.
Acre: Exactly 4840 square yards — historically a day of ploughing.
Acre to Square kilometer conversion table
| Acres (ac) | Square kilometers (km²) |
|---|---|
| 1 ac | 0.004 046 856 4 |
| 2 ac | 0.008 093 712 8 |
| 3 ac | 0.012 140 569 |
| 5 ac | 0.020 234 282 |
| 10 ac | 0.040 468 564 |
| 20 ac | 0.080 937 128 |
| 25 ac | 0.101 171 41 |
| 50 ac | 0.202 342 82 |
| 100 ac | 0.404 685 64 |
| 250 ac | 1.011 714 1 |
| 500 ac | 2.023 428 2 |
| 1000 ac | 4.046 856 4 |
Square kilometer to Acre conversion table
| Square kilometers (km²) | Acres (ac) |
|---|---|
| 1 km² | 247.105 38 |
| 2 km² | 494.210 76 |
| 3 km² | 741.316 14 |
| 5 km² | 1235.5269 |
| 10 km² | 2471.0538 |
| 20 km² | 4942.1076 |
| 25 km² | 6177.6345 |
| 50 km² | 12 355.269 |
| 100 km² | 24 710.538 |
| 250 km² | 61 776.345 |
| 500 km² | 123 552.69 |
| 1000 km² | 247 105.38 |
Frequently asked
How many square kilometers are in a acre?
One acre equals 0.004046856422 square kilometers (ac → km²). That figure is exact, not rounded.
How do you convert acres to square kilometers?
Multiply the number of acres by 0.0040468564224 to get square kilometers.
What is 1 km² in acres?
One square kilometer is 247.1053815 acres.
What is 10 ac in km²?
10 ac = 0.040 468 564 km².
What exactly is a acre?
Exactly 4840 square yards — historically a day of ploughing.