Convert Kilometer to Mile
Convert kilometers to miles instantly. 1 kilometer = 0.6213711922 mile — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Mile to Kilometer converter for the reverse conversion.
Units explained
Kilometer
A kilometer is a metric unit of length equal to one thousand meters. It is the standard unit for measuring road distances, geographic distances, and other large-scale measurements in metric countries.
The kilometer was defined alongside the meter in 1795 using the standard SI prefix kilo- (from Greek chilioi, "thousand"), denoting one thousand units.
Kilometers are used worldwide (except the United States and a few others) for road signage, geographic distance, athletic events, and scientific distances at planetary scale. Speed limits in most countries are given in km/h.
Adopted 1795 in France as part of the original metric system; the kilometer became the global standard for road and geographic distance through the 19th and 20th century metric adoption.
Mile
A mile (statute mile) is an Imperial and US customary unit of length equal to 5,280 feet or exactly 1,609.344 meters. It is the standard unit for road distances in the United States and the United Kingdom.
The mile derives from the Roman mille passus ("thousand paces" — about 1,480 meters). The English statute mile was fixed at 5,280 feet by the Weights and Measures Act of 1593, and exactly defined as 1,609.344 m by the 1959 International Yard and Pound Agreement.
Miles are used in the US and UK for road signs, speed limits (mph), athletic events (one-mile run), and geographic distances. Aviation also uses statute miles for some visibility measurements.
Roman origin (mille passus); English statute mile fixed at 5,280 feet in 1593; standardized to 1,609.344 m exactly by the 1959 International Yard and Pound Agreement.
Kilometer to Mile conversion formula
The relationship between kilometers and miles:
To convert kilometers to miles, multiply the value in kilometers by 0.6213711922. To reverse, multiply miles by 1.609344.
How to use this converter
Type a value into the calculator. The result in miles updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Mile to Kilometer converter for the reverse direction.
Step-by-step: convert kilometers to miles
- Write down the value in kilometers (km).
- Multiply that value by the factor 0.6213711922.
- The product is the equivalent value in miles (mi).
- To reverse, multiply the mile value by 1.609344.
Worked examples
Example 1 — Convert 1 km to mi:
1 × 0.6213711922 = 0.6213711922 mi
Example 2 — Convert 100 km to mi:
100 × 0.6213711922 = 62.1371192237 mi
Real-world example — European road-sign distances
A 100-km road-sign distance equals 62.14 miles. American drivers reading European or Asian highway signs convert km to miles every time they plan a tank-of-petrol's range or estimate arrival time.
100 km × 0.6213711922 = 62.1371192237 mi
Real-world example — Marathon distance in miles
The 42.195-km marathon distance equals 26.22 miles — the iconic conversion every marathon runner internalises. Converting km to miles bridges international Olympic events and US-localised local races.
42.2 km × 0.6213711922 = 26.2218643124 mi
Real-world example — Five-kilometre run for US runners
A 5-km race equals 3.107 miles — the typical 'starter' distance that runners building up from couch-to-5K progress through. Converting km to miles helps US runners visualise the distance against familiar mile markers.
5 km × 0.6213711922 = 3.1068559612 mi
Kilometer to Mile conversion table
Standard reference values for converting kilometers to miles:
| Kilometer [km] | Mile [mi] |
|---|---|
| 0.01 | 0.0062137119 |
| 0.1 | 0.0621371192 |
| 1 | 0.6213711922 |
| 2 | 1.2427423845 |
| 3 | 1.8641135767 |
| 4 | 2.4854847689 |
| 5 | 3.1068559612 |
| 10 | 6.2137119224 |
| 20 | 12.4274238447 |
| 30 | 18.6411357671 |
| 40 | 24.8548476895 |
| 50 | 31.0685596119 |
| 100 | 62.1371192237 |
| 500 | 310.6855961187 |
| 1000 | 621.3711922373 |
Frequently asked questions
How many miles is 1 kilometer?
How do I convert kilometers to miles?
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How many miles is 100 kilometers?
Popular length unit conversions
Convert Kilometer to other length units
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Metric / SI (17 units)
Imperial / US Customary (27 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 km = 0.6213711922 mi) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.