Speed Converter

Convert between miles per hour, kilometers per hour, meters per second, feet per second, knots, and Mach instantly. All processing happens client-side.

Common Reference Speeds

Walking Speed
3.1 mph
4.988962 km/h
City Speed Limit
30 mph
48.280281 km/h
Highway Speed
65 mph
104.607276 km/h
Usain Bolt (Top Speed)
27.8 mph
44.739727 km/h
Commercial Airplane
575 mph
925.37206 km/h
Speed of Sound (Mach 1)
767.269148 mph
1234.799012 km/h
Speed of Light
670616629.384395 mph
1079251985.398412 km/h
International Space Station
17150 mph
27600.22752 km/h

Click a card to load it as input

How to Use the Speed Converter

  1. Enter a speed value in the input field.
  2. Select the unit you are converting from (e.g., mph, km/h, knots).
  3. Converted values for all other units appear instantly below.
  4. Click any reference point to load it as the input value.

Speed Units Explained

Miles per hour (mph) is used in the US and UK for road speeds. Kilometers per hour (km/h) is the standard in most other countries. Knots are used in aviation and maritime navigation. Mach numbers express speed relative to the speed of sound (approximately 343 m/s at sea level and 20 degrees Celsius).

Features

  • Real-time conversion between 6 speed units
  • Conversion formulas displayed for each unit pair
  • Quick-access common reference speeds
  • One-click copy of any result
  • 100% client-side processing for full privacy