How to convert km/h to mph
Divide the speed by 1.609344.
1
Enter the speed
Use the figure from a speedometer, treadmill or weather report.
2
Read mph
The main result is in international miles per hour.
3
Add a distance
The calculator can also show the travel time at that speed.
What does this tool do?
Speed units are all ratios of distance to time. This converter uses the exact international mile and nautical mile definitions, and can also show travel time for a chosen distance.
The Formula
mph = km/h ÷ 1.609344; m/s = km/h ÷ 3.6; knots = km/h ÷ 1.852Frequently Asked Questions
How fast is 100 km/h in mph?
100 ÷ 1.609344 = 62.14 mph.
Why is a knot used at sea and in aviation?
One knot is one nautical mile per hour. The nautical mile matches a minute of latitude, which makes navigation calculations simpler.