Speed Converter

To convert miles per hour to kilometers per hour, multiply by 1.60934. For example, 60 mph equals approximately 96.56 km/h. This conversion is commonly needed for speed limits and vehicle speedometers between the US and metric countries.

A knot is one nautical mile per hour, used in aviation and maritime navigation. One knot equals approximately 1.151 mph or 1.852 km/h. So 100 knots is about 115 mph or 185 km/h.

The speed of sound in air at 20°C is approximately 343 m/s, which equals about 1235 km/h or 767 mph. Aircraft that travel faster than this are said to be supersonic.

100 km/h equals approximately 62.14 mph. This is a common reference point since 100 km/h is the typical motorway speed limit in many European countries. It is roughly equivalent to 60 mph on US highways.

Feet per second (fps) is a speed unit used in US engineering, ballistics, sports science and fluid dynamics. Walking pace is roughly 4-5 fps, highway driving is about 88-132 fps, and the speed of sound is approximately 1125 fps.