SmartKitio

MPH to KM/H Converter

Convert miles per hour (mph) to kilometers per hour (km/h). One mile per hour equals 1.60934 kilometers per hour, so multiply a value in miles per hour by 1.60934 to get kilometers per hour.

Formula: multiply the source value by 1.609344

Quick Conversions

About this tool

One mile per hour is 1,609.344 meters covered in 3,600 seconds. One kilometer per hour is 1,000 meters covered in 3,600 seconds.

How to use it

  1. Type a value in miles per hour in the first field. The unit menus start on mph → km/h.
  2. Read the result in kilometers per hour. It updates as you type; use Precision to choose how many decimals are shown.
  3. Press the swap button, or open the KM/H to MPH converter, to convert kilometers per hour back to miles per hour.
km/h = mph × 1.609344 mph = km/h ÷ 1.609344

Examples

  • 30 mph to km/h

    30 mph × 1.60934 = 48.2803 km/h.

  • 60 mph to km/h

    60 mph × 1.60934 = 96.5606 km/h.

  • 70 mph to km/h

    70 mph × 1.60934 = 112.654 km/h.

Miles per hour to kilometers per hour conversion table

Miles per hour (mph)Kilometers per hour (km/h)
11.60934
23.21869
34.82803
46.43738
58.04672
1016.0934
1524.1402
2032.1869
2540.2336
5080.4672
100160.934
250402.336
500804.672
1,0001,609.34

Kilometers per hour to miles per hour (reverse)

Kilometers per hour (km/h)Miles per hour (mph)
10.621371
53.10686
106.21371
5031.0686
10062.1371

FAQ

How many kilometers per hour are in one mile per hour?
One mile per hour is 1.60934 kilometers per hour. The unrounded factor is 1.609344.
How do I convert kilometers per hour back to miles per hour?
Divide by 1.60934, or multiply by 0.621371. For example, 10 km/h is 6.21371 mph.
Is multiplying by 1.6 good enough?
For a rough estimate, yes. The exact factor is 1.609344, so ×1.6 undercounts by about 0.6%. At 70 mph that gives 112 km/h instead of 112.65 km/h.
Is the conversion exact?
Yes, before rounding. Each unit is an exact distance (1 km, 1,609.344 m, 1 m, or 1,852 m) over an exact time, so the factors are exact ratios.