Convert km to m

km
1000m

1 km = 1000 m

Type a value in kilometres and the answer in metres appears as you go. The conversion is exactly 1000 m to the kilometre, 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 km is exactly 1000 m — 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.

Kilometre and Metre

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.

The metre has been defined since 1983 as the distance light travels in 1/299,792,458 of a second. It is not a physical object any more; the platinum bar in Paris was retired.

kilometres to metres in practice

  • 50.45 km is 50450 m

    — the Channel Tunnel.

  • 384400 km is 384400000 m

    — the average distance to the Moon.

kilometres to metres at a glance

kmm
11000
22000
33000
55000
1010000
2020000
5050000
100100000

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

Convert km to m: common questions

How many metres are in a kilometre?

Exactly 1000. One kilometre is 1000 metres, 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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