To convert kilometers to meters (km to m), multiply by 1,000. 1 kilometer equals 1,000 m, about 3 times as much as the height of the Eiffel Tower, in Paris.
| kilometers | meters |
|---|---|
| 1 kilometer | 1,000 m |
| 2 kilometers | 2,000 m |
| 5 kilometers | 5,000 m |
| 10 kilometers | 10,000 m |
| 25 kilometers | 25,000 m |
| 50 kilometers | 50,000 m |
| 100 kilometers | 100,000 m |
| 250 kilometers | 250,000 m |
| 500 kilometers | 500,000 m |
| 1000 kilometers | 1,000,000 m |
Definition: A kilometer is 1,000 meters - the "kilo" doing the same job it does in kilogram or kilobyte.
History: The meter itself was originally defined, back in 1793 during the French Revolution, as one ten-millionth of the distance from the North Pole to the equator. Today it's defined by how far light travels in a tiny fraction of a second instead - a far more precise anchor - but either way, a kilometer has always just meant a thousand of whatever "one meter" happens to be.
Current use: Nearly everywhere on Earth measures road distances, race lengths, and everyday travel in kilometers. The US remains one of the few holdouts still measuring road trips in miles.
Definition: The base unit of length in the metric system - every other metric length (km, cm, mm) is just meters multiplied or divided by a power of ten.
History: Born out of the French Revolution's push to replace a chaotic patchwork of local, often royally-defined units with something rational and universal. In 1793, French scientists defined the meter as one ten-millionth of the distance from the North Pole to the Equator, measured along the meridian running through Paris - they actually sent surveyors out to physically measure the distance between Dunkirk and Barcelona to calculate it, a project that took years longer than planned. Today the meter is defined by something far more precise and impossible to argue with: the distance light travels in a tiny, fixed fraction of a second.
Current use: The foundation of virtually every length measurement outside the US - room dimensions, building heights, and race distances (measured in km) all build on it.
The factor is 1000.00, which is derived rather than defined, so any decimal you see has been rounded somewhere.
For mental arithmetic the factor is close enough to 1000 to use directly: multiply kilometers by 1000 and the answer is right to within a rounding error.
Going the other way, one meter is 0.001 km. Because the numbers get large quickly, a whole-number answer is almost always enough here: carrying decimals implies a precision your original measurement probably does not have.
To anchor the scale: 1 kilometer is about 1,000 m.