Why this is useful
Road signs, car rentals, flight trackers and running apps don't all use the same unit. A quick conversion avoids misjudging how far a drive or walk really is.
How it is calculated
1 mile = 1.609344 km exactly; 1 nautical mile = 1.852 km exactly.
Worked example
A 100 km drive is about 62 miles; a 26.2-mile marathon is about 42.2 km.
Common mistakes
- Confusing statute miles with nautical miles, which aviation and shipping use.
- Rounding 1.6 km per mile over long distances, which adds noticeable error.
Questions
Which countries use miles on road signs?
The United States and the United Kingdom are the best-known examples; most other countries use kilometres.
Why do flight trackers show nautical miles?
Aviation uses nautical miles because one nautical mile relates to a minute of latitude, which simplifies navigation.