Speed Converter
Convert between miles per hour, kilometers per hour, meters per second, knots, feet per second, and Mach.
About this Calculator
Convert between miles per hour, kilometers per hour, meters per second, knots, feet per second, and Mach.
Formula & Calculations
Formula
Result = Input value × (Conversion factor from unit / Conversion factor to unit), normalized to m/sWhere:
- mph=Miles per hour (1 mph = 0.44704 m/s)
- kph=Kilometers per hour (1 kph = 0.277778 m/s)
- m/s=Meters per second (base unit)
- knot=Knot / nautical mile per hour (1 knot = 0.514444 m/s)
- ft/s=Feet per second (1 ft/s = 0.3048 m/s)
- Mach=Mach at sea level (1 Mach = 343 m/s)
Assumptions
- Mach is calculated as the speed of sound at sea level (343 m/s). Actual Mach varies with altitude and temperature.
- All conversions use meters per second as the intermediate base unit.
- Knots represent nautical miles per hour (1 knot = 1.852 kph).
Calculation Examples
Example 1
Inputs:60 mph to kph
Result:96.5606 kph
60 mph × 1.60934 = 96.5606 kph.
Example 2
Inputs:100 kph to m/s
Result:27.7778 m/s
100 kph ÷ 3.6 = 27.7778 m/s.
Frequently Asked Questions
Is Mach speed constant?
No. This calculator uses 343 m/s (speed of sound at sea level, 20°C). At higher altitudes or different temperatures, the speed of sound changes.
What is a knot and how is it used?
A knot equals one nautical mile per hour (1.852 kph). It is the standard unit for maritime and aviation speed measurements.