Square Miles to Square Kilometers Converter

Square Miles to Square Kilometers Converter

Square Kilometers
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Acres
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1 mi² = 2.58999 km² · 1 mi² = 640 acres

How to convert square miles to square kilometers

To convert square miles to square kilometers, multiply by 2.58999. For example, 10 mi² × 2.58999 = 25.900 km². Going the other way, multiply square kilometers by 0.386102 to get square miles.

To convert square miles to acres, multiply by 640. So 1 mi² × 640 = 640 acres.

1 mi² = 2.58999 km² = 640 acres = 258.999 hectares. Square miles are used in the US and UK for large area measurements. Square kilometers are used internationally.

Square miles to square kilometers conversion table

Square Miles (mi²) Square Kilometers (km²) Acres
1 mi²2.590 km²640 ac
2 mi²5.180 km²1280 ac
5 mi²12.950 km²3200 ac
10 mi²25.900 km²6400 ac
50 mi²129.500 km²32,000 ac
100 mi²258.999 km²64,000 ac
500 mi²1294.99 km²320,000 ac
1000 mi²2589.99 km²640,000 ac

Frequently asked questions

How many square kilometers is 1 square mile?
1 mi² = 2.58999 km² = 640 acres = 258.999 hectares.
How many square miles is 1 square kilometer?
1 km² = 0.386102 mi². Calculation: 1 ÷ 2.58999 = 0.386 mi².
How big is the US in square miles and square kilometers?
The US covers approximately 3,796,742 mi² = 9,833,520 km², making it the 4th largest country by area.
How many acres is 1 square mile?
1 square mile = exactly 640 acres = 2.58999 km² = 258.999 hectares.
How many square miles is 100 square kilometers?
100 km² = 38.610 mi². Calculation: 100 × 0.386102 = 38.610 mi².