UNIT CONVERSION · CALCULATED FROM DEFINITIONS

MPH to KM/H Converter

Convert miles per hour and kilometres per hour, with speed limits by country.

Formulakm/h = mph × 1.609344
Ratio1 mph = 1.609344 km/h

Every unit in this category

m/s0.44704Metres per second
km/h1.609344Kilometres per hour
kn0.868976242Knot
ft/s1.466667Feet per second

Common values

mphkm/h
0.5 mph0.804672 km/h
1 mph1.609344 km/h
2 mph3.218688 km/h
3 mph4.828032 km/h
5 mph8.04672 km/h
10 mph16.09344 km/h
15 mph24.14016 km/h
20 mph32.18688 km/h
25 mph40.2336 km/h
30 mph48.28032 km/h
50 mph80.4672 km/h
75 mph120.7008 km/h
100 mph160.9344 km/h
150 mph241.4016 km/h
200 mph321.8688 km/h
500 mph804.672 km/h
1000 mph1,609.344 km/h

About this tool

Enter mph to get km/h; the fields are linked both ways. Hiring a car, reading a US-market dashboard, or following British and American news all run into the mismatch: the United States and the United Kingdom use mph while Taiwan, Japan, and continental Europe use km/h. The factor comes straight from the definition of the mile as 1609.344 metres, so the result is exact. The table covers the speed limits that come up most.

How it works

  1. Enter a speed in mph, or type directly into the km/h field.
  2. Use the swap control to reverse the direction.
  3. Check the table for common speed limits.

Precision and definitions

One mile per hour is exactly 1.609344 km/h, which follows from the definition of the mile.

Privacy

Every conversion runs inside this browser. The values you enter are never uploaded, stored, or written to the URL or any log.

Frequently asked questions

What is 60 mph in km/h?
About 96.56 km/h, close to the 100 km/h limit common on Taiwanese motorways. Going the other way, 100 km/h is about 62.14 mph. Multiplying mph by 1.6 is a good mental estimate.
How does a knot relate to mph?
A knot is one nautical mile per hour, which is 1.852 km/h or about 1.15078 mph. Aviation and shipping use knots because a nautical mile matches one minute of latitude, which keeps navigation arithmetic simple. Knots are included in the speed category here.