Speed Converter

Convert speed between km/h, mph, metres per second, knots and Mach.

What is the Speed Converter?

Speed is distance per unit of time. Indian road signs use km/h, while aviation and shipping use knots.

How does it work?

Every unit is defined by an exact factor relative to the metre per second. The value is converted to the metre per second and then to the target unit, so any pair of units can be converted consistently. Results are shown with up to 10 significant digits.

Formula

1 km/h = 0.2778 m/s
1 mph = 1.609344 km/h
1 knot = 1.852 km/h

Example

100 km/h = 62.14 mph = 27.78 m/s.

Frequently asked questions

What is Mach 1?

The speed of sound, about 1,225 km/h at sea level and 15 °C. It varies with temperature and altitude.

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