Full name: kilometre
Plural form: kilometres
Symbol: km
Alternate spelling: kilometers
Category type: length
Scale factor: 1000
The SI base unit for length is the metre.
1 metre is equal to 0.001 kilometers.
Valid units must be of the length type.
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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.