Acres to square kilometers

square kilometers = acres × 0.00404686

How to convert acres to square kilometers

One acre is 0.00404686 square kilometers, so multiply the number of acres by 0.00404686. For example, 20 acres is 20 × 0.00404686 = 0.08093713 square kilometers. To go back, divide by the same number, or multiply by 247.105381.

Quick estimate

Multiplying by about 0.004 gets within 1.2% of the exact answer, which is enough to check that a result makes sense.

Where it comes up

Area conversions come up when buying flooring, paint or turf, comparing house and flat sizes, and measuring land and gardens.

acres	square kilometers
1 ac	0.00404686 km2
2 ac	0.00809371 km2
3 ac	0.01214057 km2
4 ac	0.01618743 km2
5 ac	0.02023428 km2
6 ac	0.02428114 km2
7 ac	0.02832799 km2
8 ac	0.03237485 km2
9 ac	0.03642171 km2
10 ac	0.04046856 km2
11 ac	0.04451542 km2
12 ac	0.04856228 km2
13 ac	0.05260913 km2
14 ac	0.05665599 km2
15 ac	0.06070285 km2
16 ac	0.0647497 km2
17 ac	0.06879656 km2
18 ac	0.07284342 km2
19 ac	0.07689027 km2
20 ac	0.08093713 km2
25 ac	0.10117141 km2
30 ac	0.12140569 km2
40 ac	0.16187426 km2
50 ac	0.20234282 km2
60 ac	0.24281139 km2
70 ac	0.28327995 km2
75 ac	0.30351423 km2
80 ac	0.32374851 km2
90 ac	0.36421708 km2
100 ac	0.40468564 km2
120 ac	0.48562277 km2
150 ac	0.60702846 km2
200 ac	0.80937128 km2
250 ac	1.011714 km2
300 ac	1.214057 km2
400 ac	1.618743 km2
500 ac	2.023428 km2
750 ac	3.035142 km2
1,000 ac	4.046856 km2
1,500 ac	6.070285 km2
2,000 ac	8.093713 km2
5,000 ac	20.234282 km2
10,000 ac	40.468564 km2

Questions

How many square kilometers are in a acre?

0.00404686 square kilometers.

How do I convert acres to square kilometers in a spreadsheet?

Put the value in A1 and type =A1*0.00404686, then fill the formula down the column.

Are the values in the table exact?

They are calculated from the exact definitions of the units and rounded only for display. Open any row for the full working.