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Speed can be measured in multiple units depending on context. Miles per hour (mph) is used in the US and UK for road speeds. Kilometres per hour (kph) is the metric standard used globally. Knots are used in aviation and maritime navigation. Metres per second (m/s) is the scientific standard.
Understanding speed conversions is essential for travel, driving, aviation, and physics. Each unit has its own conversion factor, but all represent the same fundamental measurement: distance travelled per unit of time.
Our converters handle all common speed conversions instantly and accurately. Whether you're converting speed limits, aircraft velocity, or calculating physics problems, you can rely on these tools.
Some reference points to help you understand speed measurements:
A knot is a unit of speed used in aviation and maritime navigation. 1 knot = 1 nautical mile per hour. It's approximately 1.15 mph or 1.85 km/h. Knots are preferred for aviation and sea travel because they relate to latitude and longitude.
The speed of sound at sea level is approximately 761 mph (1,235 km/h or 340 m/s). It varies slightly with temperature and altitude. Aircraft travelling faster than this are said to be supersonic.
Countries that use the metric system (most of the world) measure speed in km/h. The US and UK use mph. Aviation and maritime industries use knots internationally for consistency with navigation systems.
m/s stands for metres per second, the SI (scientific) unit of speed. It's the standard in physics and engineering. 1 m/s = 3.6 km/h = 2.237 mph.
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