Speed Converter
Convert between m/s, km/h, mph, ft/s, knots, and Mach.
m/s (meters/second)
27.777778
km/s (kilometers/second)
0.027777778
km/h (kilometers/hour)
100
mph (miles/hour)
62.137119
ft/s (feet/second)
91.134442
Knot (nautical mi/h)
53.995727
Mach (speed of sound)
0.080984775
Speed of light (c)
9.265669e-8
About This Tool
The Speed Converter converts between 8 speed units: m/s, km/s, km/h, mph, ft/s, knots, Mach, and the speed of light. Enter a value and select the source unit — all conversions appear instantly.
Mach uses the speed of sound at sea level, 20°C (343 m/s). Very large or small values are displayed in exponential notation.
How to Use
- Enter the speed value you want to convert.
- Select the source unit from the dropdown.
- All unit conversions appear automatically.
- Note or copy the result you need.
Use Cases
Pilots and navigators convert between km/h and knots. Automotive engineers compare m/s and mph. Physicists check relativistic speeds against the speed of light.
FAQ
- What exactly is Mach 1? — Approximately 343 m/s (1,235 km/h) at sea level, 20°C. It varies with altitude and temperature.
- What is a knot? — 1 knot = 1 nautical mile per hour (1,852 m/h), used in aviation and maritime navigation.
- Why is the speed of light result so large? — The speed of light is 299,792,458 m/s. Very large values are shown in exponential notation (e.g., 1.08e9 km/h).