Convert Square Miles to Square Kilometers

Convert square miles to square kilometers instantly. Type a value below, check the formula and table, then see how the same mi² to km² conversion looks as a single line in Notes Calculator.

Square Miles to Square Kilometers formula

One square mile is 2.58999 square kilometers, so km² = mi² × 2.58999. For the reverse, multiply square kilometers by 0.386102, or use the Square Kilometers to Square Miles converter.

Square Miles to Square Kilometers conversion table

Square Miles to Square Kilometers in Notes Calculator

Notes Calculator is a notepad that does math. Write 100 square miles to square kilometers on any line and the answer appears beside it. Change the number and the result follows. The same works with in and as, and with values stored in variables, so a whole estimate can mix square miles and square kilometers without a separate converter.

Square Miles to Square Kilometers

Square Miles to Square Kilometers

Note	Result
1 100 square miles to square kilometers	259.00 km²
2 100 square miles in square kilometers	259.00 km²
3 10 square kilometers as square miles	3.86 mi²

See the unit conversion docs for mixing units in one expression, or open the free web app and try it.

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• Square Miles to Square Yards
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