speed converter
convert speed between mph, km/h, m/s, knots and other units.
runs on your device · free · no sign-up
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frequently asked questions
how do i convert mph to km/h?
multiply miles per hour by 1.609344.
what is a knot?
one nautical mile per hour, equal to 1.852 km/h or about 1.151 mph.
is the mach number fixed?
no, it depends on air temperature. this tool uses 340.29 m/s, the speed of sound at sea level at 15 °C.