To convert meters to kilometers (m to km), multiply by 0.001. 1 meter equals 0.001 km, about 1.4 times as much as a tennis racket.
| meters | kilometers |
|---|---|
| 1 meter | 0.001 km |
| 2 meters | 0.002 km |
| 5 meters | 0.005 km |
| 10 meters | 0.01 km |
| 25 meters | 0.025 km |
| 50 meters | 0.05 km |
| 100 meters | 0.1 km |
| 250 meters | 0.25 km |
| 500 meters | 0.5 km |
| 1000 meters | 1 km |
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.
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.