Convert mi to km

mi
1.609344km

1 mi = 1.609344 km

Type a value in miles and the answer in kilometres appears as you go. The conversion is exactly 1.609344 km to the mile, and it happens on your own machine — this page asks nothing of a server once it has loaded.

  • Where it runs

    In your browser. The number you type is never part of a request.

  • Exact by definition

    1 mi is exactly 1.609344 km — a definition, not a rounded factor.

  • Answers as you type

    No button, no wait. The worked answer is already on the page before any script runs.

Mile and Kilometre

A mile is 1,760 yards — a number that comes from a Roman thousand paces, adjusted by an Elizabethan statute to fit the furlong. It is exactly 1,609.344 metres.

Kilometres are the road distance nearly everywhere outside the United States and the United Kingdom, which is why converting them is usually about reading a map or a race entry.

miles to kilometres in practice

  • 26.219 mi is 42.2 km

    — a marathon.

  • 3 mi is 4.828 km

    — a short commute.

miles to kilometres at a glance

mikm
11.609344
23.218688
34.828032
58.04672
1016.09344
2032.18688
5080.4672
100160.9344

Every figure here is computed from the same definition the calculator uses, so the table cannot drift away from the answer above it.

Convert mi to km: common questions

How many kilometres are in a mile?

Exactly 1.609344. One mile is 1.609344 kilometres, and the box above will do it for any figure you type.

Is this conversion exact, or rounded?

The ratio is exact. It is not a rounded constant typed into a table: it is derived from the definitions of the two units, so it agrees with any other correct converter to as many digits as you care to compare.

Why does another converter show a slightly different number?

Almost always rounding rather than disagreement. Many converters cut the answer to two or four decimals, and some carry a factor that was rounded before the multiplication rather than after. The figures here are computed from the exact definitions and only rounded on the way to the screen.

Where these figures come from

The claims this page makes about length units are checkable, and these are the documents that settle them.

How this page works

The factor is a constant in the page and the arithmetic is four operations, so nothing is sent anywhere and nothing needs to be. The number you type never leaves the browser — there is no request for it to travel in.

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