How many mm in 1 kilometer?
The answer is 1000000.
We assume you are converting between millimetre and kilometre.
You can view more details on each measurement unit: mm or
kilometer
The SI base unit for length is the metre.
1 metre is equal to 1000 mm, or 0.001 kilometer.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between millimetres and kilometres.
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A millimetre (American spelling: millimeter, symbol mm) is one thousandth of a metre, which is the International System of Units (SI) base unit of length. The millimetre is part of a metric system. A corresponding unit of area is the square millimetre and a corresponding unit of volume is the cubic millimetre.

Definition: Kilometer

A kilometre (American spelling: kilometer, symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure). It is approximately equal to 0.621 miles, 1094 yards or 3281 feet.

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