Skip to content

MPH to km/h Converter

Convert miles per hour to kilometers per hour and back. 1 mile per hour = 1.609344 kilometers per hour exactly.

Speed converter
Type an amount. Use the tabs to switch direction.
mph
Result: Km/h
96.56064kilometers per hour
1 mph = 1.609344 km/h
Also equals
26.8224 m/s
Meters Per Second
52.138575 kn
Knots
Learn how we calculate this below

Tip: Results show up to 8 significant digits. The factors and their sources are listed on the "Where our numbers come from" page.

Updated

On this page
  1. MPH and km/h
  2. Quick conversion table
  3. Exact factor and source
  4. How to convert miles per hour to kilometers per hour
  5. All speed units compared
  6. What is a mile per hour?
  7. What is a kilometer per hour?
  8. What this converter does not do
  9. Frequently asked questions
  10. References
  11. Related converters

MPH and km/h

One mile per hour is exactly 1.609344 kilometers per hour, and one kilometer per hour is about 0.621371192237 miles per hour. The converter works both ways: use the two tabs at the top of the tool to choose the direction.

Quick conversion table

MPH to km/h

MPHkm/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
40 mph64.37376 km/h
50 mph80.4672 km/h
55 mph88.51392 km/h
60 mph96.56064 km/h
65 mph104.60736 km/h
70 mph112.65408 km/h
75 mph120.7008 km/h
80 mph128.74752 km/h
100 mph160.9344 km/h

km/h to MPH

km/hMPH
10 km/h6.2137119 mph
20 km/h12.427424 mph
30 km/h18.641136 mph
40 km/h24.854848 mph
50 km/h31.06856 mph
60 km/h37.282272 mph
80 km/h49.709695 mph
90 km/h55.923407 mph
100 km/h62.137119 mph
110 km/h68.350831 mph
120 km/h74.564543 mph
130 km/h80.778255 mph
150 km/h93.205679 mph

Exact factor and source

ConversionValueBasis
1 mile per hour in kilometers per hour1.609344exact. NIST SP 811 (2008), Appendix B.8: 1 mi/h = 1609.344 m / 3600 s = 0.44704 m/s exactly
1 kilometer per hour in miles per hour0.621371192237rounded to 12 digits. 1 km/h = 1000 m / 3600 s = 1/3.6 m/s exactly (SI Brochure: hour = 3600 s)

How to convert miles per hour to kilometers per hour

  1. Step oneTake the number of miles per hour.
  2. Step twoMultiply it by 1.609344.
  3. Step threeThe result is the number of kilometers per hour.
  4. Step fourTo go back, divide by 1.609344, or multiply by 0.621371192237.
km/h = mph x 1.609344

Example: 60 mph x 1.609344 = 96.56064 km/h.

All speed units compared

Each unit written in meters per second, the base unit of this tool. Exact values come straight from the definitions.

UnitSymbolValue in meters per second
Meters per secondm/s1 meter per second
Kilometers per hourkm/h0.277777777778 meters per second
Miles per hourmph0.44704 meters per second
Knotskn0.514444444444 meters per second

What is a mile per hour?

Miles per hour (mph) is the speed unit on road signs in the United States and the UK. One mph is exactly 1.609344 kilometers per hour, or 0.44704 meters per second.

What is a kilometer per hour?

Kilometers per hour (km/h) is the road speed unit in most of the world. One km/h is 0.621371192237 miles per hour, or about 0.277777777778 meters per second.

What this converter does not do

  • Results are rounded for display to 8 significant digits; the stored factor is the exact one.
  • It converts a speed; it does not convert a speed into a pace such as minutes per mile.
  • It does not know the speed limits of any road.

Frequently asked questions

How many kilometers per hour are in a mile per hour?

1 mile per hour is exactly 1.609344 kilometers per hour. That factor is exact by definition.

How many miles per hour are in a kilometer per hour?

1 kilometer per hour is about 0.621371192237 miles per hour.

How fast is 65 mph in km/h?

65 mph is 104.60736 km/h.

Where do the factors come from?

Miles per hour: NIST SP 811 (2008), Appendix B.8: 1 mi/h = 1609.344 m / 3600 s = 0.44704 m/s exactly. Kilometers per hour: 1 km/h = 1000 m / 3600 s = 1/3.6 m/s exactly (SI Brochure: hour = 3600 s).

References