mi² to km² Converter

Type a value in square miles and read the equivalent in square kilometres immediately, with the exact factor and common values.

How mi² to km² works

Convert square miles to square kilometres instantly. 1 mi² = 2.589988 km², with a live result and a quick reference table. Everything happens inside this page: the tool reads your input, runs the calculation or conversion locally, and hands the result back to you. Nothing is transmitted, because there is no backend to transmit it to.

That design choice is deliberate. Most free tool sites upload your files to a server, process them there, and quietly keep a copy. Toolcin cannot do that — the site is a set of static files. If your connection dropped the moment the page finished loading, every tool would still work.

What one mi² is in km²

The conversion is a single multiplication by 2.58998811, so the result is only as rounded as the display. Going the other way divides by the same figure: one km² is 0.3861021586 mi².

No intermediate rounding happens. A value entered with four decimals comes back with the same precision, which is what makes the factor trustworthy for anything that accumulates error.

Values people ask for

mi²km²
1 mi²2.58998811 km²
2 mi²5.17997622 km²
5 mi²12.94994055 km²
10 mi²25.8998811 km²
25 mi²64.74970275 km²
50 mi²129.4994055 km²
100 mi²258.998811 km²

Where this pair comes up

US and UK land data use square miles while metric countries use square kilometres.

The factor is 2.59, not 1.609 — area scales with the square of the linear factor.

Good to know

  • Works offline once loaded, including on flights and in locked-down networks.
  • No file size limit beyond your device's own memory.
  • Free to use, with no account and no usage counter.
  • Results are produced locally, so they are not logged or shared with anyone.

Questions

What is the conversion factor?

1 mi² = 2.589988 km², from the international definition.

Can I convert backwards?

Divide by 2.589988 to go the other way.

Is the factor exact?

It is the standard definition for this pair, applied without intermediate rounding. Only the displayed result is rounded.

Can I convert km² back to mi²?

Yes — divide by 2.58998811 instead of multiplying, or use the reverse page if one exists.

Keep going

More converters tools