Convert acres to square kilometers

1 ac = 0.00404686 km². Change the amount below, or read the formula and the reference table further down.

1 acre equals

0.00404686square kilometers

1 ac = 0.00404686 km²

The formula

Acres and square kilometers both measure area from the same zero, so a single multiplier does the job.

km² = ac × 0.0040468564

Going the other way? Convert square kilometers to acres.

Acres to square kilometers table

Common values, rounded for reading.

Acres (ac)Square kilometers (km²)
10.004047
20.008094
30.012141
40.016187
50.020234
60.024281
70.028328
80.032375
90.036422
100.040469
150.060703
200.080937
250.101171
300.121406
400.161874
500.202343
750.303514
1000.404686
2501.0117
5002.0234
1,0004.0469

Questions people ask

How many square kilometers are in a acre?
One acre equals 0.0040468564 square kilometers.
How do I convert acres to square kilometers by hand?
Multiply the number of acres by 0.0040468564. For a rough check, 0.004 is close enough for most everyday use.
What is 1 acre in square kilometers?
1 acre is 0.00404686 square kilometers.

Calcuit generates this page from a unit table, so the factors here match every other page on the site.

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