Speed conversions combine a distance factor and a time factor. One mile per hour is exactly 1.609344 km/h, one metre per second is exactly 3.6 km/h, and one knot (one nautical mile per hour) is exactly 1.852 km/h. Knots are standard in aviation and shipping, m/s in physics, and km/h or mph on road signs depending on the country. This tool converts between all of them as you type. Typical checks include a 100 km/h motorway limit (62.1 mph), a 10 m/s wind (36 km/h, about 19.4 knots), or a sprinter's top speed of about 12 m/s (43 km/h).
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