Square Miles to Square Kilometers converter (mi² to km²)
Convert Square Miles (mi²) to Square Kilometers (km²) with this free calculator. Type a value, press Convert, and the page applies the same factor shown in the formula below — no rounded shortcut, and nothing is stored on a server.
Square Kilometers to Square Miles (km² to mi²) ►
How to convert Square Miles to Square Kilometers
1 square mile (mi²) is equal to 2.58999 square kilometers (km²).
km² = mi² × 2.58999
Multiply the square miles by 2.58999:
Example: Convert 5 mi² to km²:
km² = 5 × 2.58999 = 12.95 km²
What is a Square Miles?
The Square Miles (mi²) is the starting or target unit on this page. Use the calculator above to convert values without looking up the factor by hand.
What is a Square Kilometers?
The Square Kilometers (km²) is the starting or target unit on this page. Use the calculator above to convert values without looking up the factor by hand.
This page converts area from Square Miles into Square Kilometers. One mi² equals 2.58999 km².
Square Miles to Square Kilometers conversion table
Common mi² values and the matching km² result, calculated with the same factor as the widget. Highlight a nearby row if you want a quick check without entering a number.
| Square Miles (mi²) | Square Kilometers (km²) |
|---|---|
| 1 mi² | 2.58999 km² |
| 5 mi² | 12.94995 km² |
| 10 mi² | 25.8999 km² |
| 50 mi² | 129.4995 km² |
| 100 mi² | 258.999 km² |
| 500 mi² | 1294.995 km² |
| 1000 mi² | 2589.99 km² |
How this calculator works
The form on this page is a Square Miles-to-Square Kilometers converter. After you enter a number, JavaScript multiplies or rearranges it with the published conversion factor and writes the km² result in the output box. The step-by-step panel repeats the arithmetic so you can copy it into homework or a spreadsheet.
Reviewed by Hamsen, founder of GigaTables and a biology engineer. See the about page for how formulas are checked before a tool is published.
FAQ
How many km² are in 1 mi²?
1 mi² = 2.58999 km².
How do I convert Square Miles to Square Kilometers?
Multiply the square miles by 2.58999:
Is this mi² to km² converter free?
Yes. GigaTables calculators are free to use in a browser. You do not need an account, and the values you type are not uploaded.