Speed
Convert between different units of speed from everyday measurements to scientific and historical units
Speed Converter
Convert between different units of speed from everyday measurements to scientific and historical units
Conversion Result
Fun Facts
About Speed
Explore the diverse ways humans have measured speed throughout history and across different fields
Historical Context
Speed measurements have evolved from simple comparisons to natural phenomena (like horse speeds) to precise scientific units. Ancient civilizations used distance-per-time units based on their local measurement systems, such as Roman miles per hour or Japanese ri. The development of maritime navigation introduced the knot, while modern physics brought us concepts like Mach numbers and the speed of light as a universal constant.
Modern Standards
Today, meters per second (m/s) is the SI unit for speed, though kilometers per hour (km/h) is more common for everyday use in most countries. The United States and United Kingdom still primarily use miles per hour (mph) for road speeds. Specialized fields maintain their own units: aviation and maritime navigation use knots, while aerospace engineering uses Mach numbers to describe speeds relative to sound.
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Conversion Reference
Quick reference for common speed conversions