What is kilometre?
A kilometre is a metric unit of length equal to 1,000 metres. It is the standard unit for road distances, route planning, and geographic measurements in most countries.
Real-world uses
Kilometres are the standard unit for road distances, city-to-city navigation, and speed limits in most countries outside the United States. Marathon runners track their pace in minutes per kilometre, and GPS devices report distances in km.
History
Introduced as part of the metric system in France in 1795. The prefix "kilo-" comes from the Greek word "chilioi" meaning thousand. It became the global standard for road distances as the metric system spread in the 19th and 20th centuries.
Common mistakes
Assuming 1 mile equals 1 kilometre—a mile is actually about 1.609 km. Another error is mispronouncing it as "kil-AH-meter" instead of "KIL-o-metre," which changes the implied meaning.
What is foot?
A foot is a unit of length in imperial and US customary systems equal to 12 inches. It is commonly used in construction, architecture, body height measurements, and aviation for altitude references.
Real-world uses
Feet are the primary unit for building dimensions, room sizes, and ceiling heights in the United States. Aviation uses feet for altitude worldwide (e.g., cruising at 35,000 ft). Human height in the US and UK is commonly expressed in feet and inches.
History
The foot has been used since ancient civilizations, with varying lengths based on the local king's foot. The modern international foot was defined in 1959 as exactly 0.3048 metres, replacing slightly different US and British survey definitions.
Common mistakes
Using an apostrophe for feet (6') and confusing it with the prime symbol. Also, people often round 1 foot to 30 cm instead of the correct 30.48 cm, leading to cumulative errors in construction.
When is this conversion used?
Converting between kilometre and foot is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region. This conversion is frequently needed in construction, architecture, and real estate where building codes may specify dimensions in one system while materials are sold in another. Road distances and speed limits are posted in kilometres in most countries and miles in the US and UK, making this conversion essential for international drivers and route planning.
Worked examples
1 kilometre = 3,280.83989501 foot
1 foot = 0.3048 metre
How to convert kilometre to foot
To convert kilometre to foot, multiply the value by 3,280.83989501.
To convert foot back to kilometre, multiply by 0.0003048.
Measurement standards
The metre is one of seven SI base units, maintained by the International Bureau of Weights and Measures (BIPM). Since 2019, it is defined by fixing the numerical value of the speed of light in vacuum to exactly 299,792,458 metres per second.
Did you know?
A human hair is roughly 70 micrometres wide, while a single gold atom measures about 0.144 nanometres in diameter — meaning you could line up nearly half a million atoms across the width of one hair.
Quick reference: kilometre to foot
| kilometre | foot |
|---|---|
| 0.1 | 328.0839895 |
| 0.5 | 1,640.41994751 |
| 1 | 3,280.83989501 |
| 2 | 6,561.67979003 |
| 5 | 16,404.19947507 |
| 10 | 32,808.39895013 |
| 25 | 82,020.99737533 |
| 50 | 164,041.99475066 |
| 100 | 328,083.98950131 |
| 250 | 820,209.97375328 |
| 500 | 1,640,419.94750656 |
| 1,000 | 3,280,839.89501312 |
Common values
| kilometre | foot | |
|---|---|---|
| Height of a door | 0.0021 kilometre | 6.88976378 foot |
| Basketball court length | 0.028 kilometre | 91.86351706 foot |
| Football field (soccer) | 0.105 kilometre | 344.48818898 foot |
| Marathon distance | 42.195 kilometre | 138,435.03937008 foot |
| Altitude of a cruising airplane | 10.668 kilometre | 35,000 foot |