Square miles to Square kilometers Converter
Convert square miles to square kilometers instantly. Exact factor: 1 mi² = 2.59 km².
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Convert square miles to square kilometers
The exact conversion factor is 1 mi² = 2.59 km². Type any value and the result updates instantly; the math is shown beneath the board.
Worked by hand
Multiply the square miles value by 2.59 to get square kilometers.
Worked example
- Take 1 mi²
- multiply by 2.59
- the result is 2.59 km²
How to use it
- Enter your square miles
- Read the square kilometers result
- Check the factor line to verify by hand
Frequently asked questions
How many square kilometers are in one square miles?
Exactly 2.59 km², by the SI/NIST definition.
How do I convert square kilometers back to square miles?
Divide by 2.59 — or use the full converter where both directions are one click.
Is this rounding or exact?
The factor is exact; only the displayed decimals are rounded.