How to Convert / Calculate Kilometers Km to Miles Mi

Kilometers are standard on road signs in many countries.

Maps and road signs in the U.S. generally use miles to measure distance, but most of the world uses the metric system of units, where kilometers are the standard unit of distance. If you are planning to travel in other countries, converting from kilometers to miles can help you get a better idea of the distances you will be traveling from one place to the next.

Instructions

1. Set up a unit conversion equation using the conversion factor 1 mile equals 1.609 km. Make sure the units will cancel; since you are converting from km, you want to multiply by the conversion factor with km in the denominator. To convert 10 km, for example, the equation is (10)*(1/1.609).

2. Multiply the unit conversion equation to find the number of miles; cancel out the kilometer unit that appears in the numerator and denominator, so you are left with only the mile unit. For example, (10)*(1/1.609 )= 6.22 mi.

3. Multiply the result by 1.609 to check your work. If you calculated correctly, you should get the number of kilometers you started with.

References

• Bryn Mawr: Conversions
• NC State University; One of These Things Is Not Like the Other: A Discussion of Units; Kenny Fleder; 1996

Resources

• Read this Article in Spanish
• Carleton College; Unit Conversions Practice Problems; October 2009