American road signs, speedometers and running apps speak in miles while most of the world uses kilometers. This converter covers all of them — including nautical miles for aviation and marine charts, which are a different unit entirely.
The km to miles formula
1 mile = 1.609344 kilometers, so 1 km ≈ 0.6214 miles. Kilometers to miles: multiply by 0.6214. Miles to kilometers: multiply by 1.6093. A reliable mental trick: remember that 5 miles ≈ 8 km, and scale from there — 10 miles ≈ 16 km, 15 miles ≈ 24 km.
Nautical miles are different
A nautical mile equals 1.852 km (about 1.15 land miles) and is based on one minute of Earth latitude. Ships and planes measure distance in nautical miles and speed in knots (one nautical mile per hour). Do not mix them with statute miles.
Running distances at a glance
5K ≈ 3.11 mi · 10K ≈ 6.21 mi · Half marathon 21.0975 km ≈ 13.11 mi · Marathon 42.195 km ≈ 26.22 mi. When an American runner mentions a "10-miler", that is about 16 km.