How to convert kilometers/hour to miles/hour

Step-by-step explanation of how to convert kilometers/hour to miles/hour, with formulas, worked examples, and a free online calculator.

To convert kilometers per hour to miles per hour, divide by 1.609344. The formula is: mph = km/h ÷ 1.609344. For example, 100 km/h ÷ 1.609344 = 62.14 mph. This conversion is useful for US drivers reading European speed limits, or for international runners and cyclists. The quick mental math: divide km/h by 1.6 for an approximate mph. For reference, 50 km/h ≈ 31 mph, 80 km/h ≈ 50 mph, 120 km/h ≈ 75 mph.