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Speed Converter - Convert MPH, KPH & More

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Speed Converter

Easily convert between Kilometers per Hour (km/h), Miles per Hour (mph), Meters per Second (m/s), Feet per Second (ft/s), Knots (kt), and Mach. Whether you're measuring car speed, aircraft velocity, or physics experiment values, this tool gives you fast and accurate conversions.

Why Use It?

  • Ideal for travel, sports timing, aeronautics, and scientific calculations.
  • Converts between metric and imperial speed units.
  • Accurate to four decimal places.
  • Great for students, pilots, athletes, and engineers alike.

Popular Conversions

Supported Units

  • Kilometers per Hour (km/h) - Commonly used for road speeds and travel distances in most countries.
  • Miles per Hour (mph) - Standard unit for speed in the US and UK road systems.
  • Meters per Second (m/s) - SI unit of speed; widely used in science and engineering.
  • Feet per Second (ft/s) - Used in ballistics and physics calculations in imperial contexts.
  • Knots (kt) - Used in maritime and aviation contexts; 1 knot = 1 nautical mile per hour.
  • Mach - Speed relative to the speed of sound; used for aircraft and high-speed aerospace vehicles.

Common Uses

  • Converting car or bike speeds while traveling abroad
  • Aviation and marine navigation
  • Analyzing athletic performance in races or training
  • Solving physics and engineering problems
  • Comparing vehicle and wind speeds across different units
  • Calculating sound barrier speeds in aerospace studies

Frequently Asked Questions

What is Mach speed?

Mach is a ratio comparing an object's speed to the speed of sound in air. Mach 1 equals the speed of sound (approx. 343 m/s or 1,235 km/h) at sea level under standard atmospheric conditions.

How many mph is 100 km/h?

100 kilometers per hour is approximately 62.1371 miles per hour.

Why do airplanes use knots instead of km/h or mph?

Knots are based on nautical miles, which relate closely to lines of latitude and longitude. This makes them especially useful for navigation over the Earth's curved surface.

Are m/s and km/h interchangeable?

They measure the same quantity (speed), but 1 m/s = 3.6 km/h. So, they are not numerically equivalent and require conversion.