How do I convert acres to square kilometers?

Multiply the acre value by 0.00404686. So x ac × 0.00404686 = the equivalent in km².

What is 5 acres in square kilometers?

5 acres equals 0.0202343 square kilometers.

What is 10 acres in square kilometers?

10 acres equals 0.0404686 square kilometers.

What is 100 acres in square kilometers?

100 acres equals 0.404686 square kilometers.

How do I convert back from square kilometers to acres?

Multiply the square kilometer value by 247.105. For example, 1 km² = 247.105 ac.

Is the acre bigger than the square kilometer?

No. 1 acre is smaller than 1 square kilometer. It takes 247.105 acres to equal 1 square kilometer.

Are these conversion factors exact?

Yes. Since the 1959 international yard and pound agreement, imperial/US units are defined exactly in terms of metric units, so the factor used here (0.00404686) is exact within IEEE 754 double precision.

Acres to Square kilometers Converter

1 ac = 0.00404686 km² (acre → square kilometer)

1 ac = 0.00404686 km²

1 acre equals 0.00404686 square kilometers. To convert acres to square kilometers, multiply the acre value by 0.00404686. For quick reference: 1 ac = 0.00404686 km², 5 ac = 0.0202343 km², 10 ac = 0.0404686 km², 100 ac = 0.404686 km².

From

0.00404686

FormulaSquare kilometers = Acres × 0.00404686

Quick

When to use acres → square kilometers

Acres to square kilometers divides by 247.105 (1 km² = 247.105 acres). A 10,000-acre ranch is 40.5 km². The conversion appears at the ranch-and-region scale where imperial land holdings meet metric geography — comparing a large US landholding against a national park or administrative district quoted in km². For rough work, 250 acres per km² is accurate to about 1 %.

How to convert acres to square kilometers

Take your value
Start with your value in acres.
Multiply by 0.00404686
Multiply the acre value by 0.00404686. This is the exact conversion factor from acres to square kilometers.
Read the result
The product is your value in square kilometers. For example, 5 ac × 0.00404686 = 0.0202343 km².

Conversion formula

The exact factor from acres to square kilometers is 0.00404686.

Square kilometers = Acres × 0.00404686

Acres to Square kilometers conversion table

Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.

Conversion table from acres to square kilometers
Acres (ac)	Square kilometers (km²)
0.1 ac	0.00040469 km²
0.25 ac	0.0010117 km²
0.5 ac	0.0020234 km²
1 ac	0.0040469 km²
2 ac	0.0080937 km²
3 ac	0.012141 km²
4 ac	0.016187 km²
5 ac	0.020234 km²
6 ac	0.024281 km²
7 ac	0.028328 km²
8 ac	0.032375 km²
9 ac	0.036422 km²
10 ac	0.040469 km²
12 ac	0.048562 km²
15 ac	0.060703 km²
20 ac	0.080937 km²
25 ac	0.10117 km²
30 ac	0.12141 km²
40 ac	0.16187 km²
50 ac	0.20234 km²
60 ac	0.24281 km²
70 ac	0.28328 km²
75 ac	0.30351 km²
80 ac	0.32375 km²
90 ac	0.36422 km²
100 ac	0.40469 km²
120 ac	0.48562 km²
150 ac	0.60703 km²
200 ac	0.80937 km²
250 ac	1.0117 km²
300 ac	1.2141 km²
400 ac	1.6187 km²
500 ac	2.0234 km²
600 ac	2.4281 km²
750 ac	3.0351 km²
800 ac	3.2375 km²
1000 ac	4.0469 km²
1200 ac	4.8562 km²
1500 ac	6.0703 km²
2000 ac	8.0937 km²
2500 ac	10.117 km²
3000 ac	12.141 km²
4000 ac	16.187 km²
5000 ac	20.234 km²
7500 ac	30.351 km²
10000 ac	40.469 km²
20000 ac	80.937 km²
50000 ac	202.34 km²
100000 ac	404.69 km²
1000000 ac	4046.9 km²

Real-world reference

An American football field (with end zones) is about 1.32 acres. A quarter-acre lot is the classic US suburban plot size.

Frequently asked questions

How many square kilometers are in 1 acre?: 1 acre equals 0.00404686 square kilometers.
How do I convert acres to square kilometers?: Multiply the acre value by 0.00404686. So x ac × 0.00404686 = the equivalent in km².
What is 5 acres in square kilometers?: 5 acres equals 0.0202343 square kilometers.
What is 10 acres in square kilometers?: 10 acres equals 0.0404686 square kilometers.
What is 100 acres in square kilometers?: 100 acres equals 0.404686 square kilometers.
How do I convert back from square kilometers to acres?: Multiply the square kilometer value by 247.105. For example, 1 km² = 247.105 ac.
Is the acre bigger than the square kilometer?: No. 1 acre is smaller than 1 square kilometer. It takes 247.105 acres to equal 1 square kilometer.
Are these conversion factors exact?: Yes. Since the 1959 international yard and pound agreement, imperial/US units are defined exactly in terms of metric units, so the factor used here (0.00404686) is exact within IEEE 754 double precision.

About the acre and the square kilometer

The acre

The acre is the traditional imperial unit for land, still the standard for US and UK property, farmland, and parkland. One acre is exactly 4,046.8564224 m² — historically the area a yoke of oxen could plough in a day, standardised as 1 chain by 1 furlong (66 × 660 feet, or 43,560 square feet). An American football field including end zones is about 1.32 acres.

The square kilometer

The square kilometer equals one million square meters — the standard unit for city, region, and country areas in metric countries. Manhattan is about 59 km²; Istanbul is about 5,461 km²; Turkey is about 783,562 km². One km² equals exactly 100 hectares or about 0.386 square miles.

Square kilometers to Acres

km² → ac

Square meters to Square feet

m² → ft²

Square meters to Acres

m² → ac

Square meters to Hectares

m² → ha

Square meters to Square kilometers

m² → km²

Square meters to Square miles

m² → mi²