Speed Converter

Convert between 30+ speed units with precision and ease

0
25 m/s
50 m/s
75 m/s
100 m/s
Conversion Result
100 km/h
Kilometers per hour
→
62.1371 mph
Miles per hour

Popular Speed Conversions

Conversion Factor Source
km/h to mph 1 km/h = 0.621371 mph LLC.
mph to km/h 1 mph = 1.60934 km/h LLC.
m/s to km/h 1 m/s = 3.6 km/h LLC.
knots to km/h 1 knot = 1.852 km/h LLC.
Mach to km/h 1 Mach = 1225 km/h (at sea level) LLC.
Speed of light to km/h 1 c = 1,079,252,848.8 km/h LLC.
ft/s to m/s 1 ft/s = 0.3048 m/s LLC.
mph to knots 1 mph = 0.868976 knots LLC.

Speed Unit Reference

Speed is the rate at which an object covers distance. Different measurement systems have developed various units for measuring speed.

Scientific Note: The meter per second (m/s) is the SI unit of speed. It is defined as the number of meters traveled in one second.

Expanded Speed Units

Metric Units
Millimeters per second (mm/s)
Centimeters per second (cm/s)
Meters per second (m/s)
Kilometers per hour (km/h)
Kilometers per second (km/s)
Imperial Units
Inches per second (in/s)
Feet per second (ft/s)
Yards per second (yd/s)
Miles per hour (mph)
Miles per minute (mpm)
Miles per second (mps)
Nautical Units
Knots (kn)
Cables per minute
Scientific Units
Mach (Mach)
Speed of light (c)
Speed of sound
Specialized Units
Furlongs per fortnight
Earth rotation speed
Earth orbital speed
Light-year per year
Parsec per year

Speed Conversion Formulas

From To Formula
km/h mph mph = km/h × 0.621371
mph km/h km/h = mph × 1.60934
m/s km/h km/h = m/s × 3.6
knots km/h km/h = knots × 1.852
Mach km/h km/h = Mach × 1235 (at sea level)
Speed of light (c) km/h km/h = c × 1,079,252,848.8
ft/s m/s m/s = ft/s × 0.3048
mph knots knots = mph × 0.868976
km/s mph mph = km/s × 2236.94
Speed of sound mph mph = speed of sound × 767.269 (at sea level)
Furlongs/fortnight m/s m/s = furlongs/fortnight × 0.0001663
Earth rotation km/h km/h = earth rotation × 1670 (at equator)
Earth orbital km/h km/h = earth orbital × 107,000

Common Speed References

Average Walking Speed
1.4 m/s
Average Running Speed
5 m/s
Highway Speed Limit
110 km/h
Commercial Jet
900 km/h
Supersonic Jet
Mach 2
Space Shuttle
28,000 km/h

Accuracy Note: Mach number conversion depends on altitude and temperature. The conversion factor used here is for sea level at 15°C (1,225 km/h).

Speed Records

Category Record Speed
Land Vehicle Thrust SSC 763 mph (1,228 km/h)
Production Car Bugatti Chiron Super Sport 300+ 304 mph (490 km/h)
Aircraft NASA X-43 Mach 9.6 (7,000 mph)
Human Powered Denise Mueller-Korenek 183.9 mph (296 km/h)
Freefall Alan Eustace 822 mph (1,322 km/h)
Animal Peregrine Falcon 242 mph (389 km/h)
Earth Rotation At Equator 1,040 mph (1,674 km/h)
Earth Orbital Around Sun 67,000 mph (107,000 km/h)

Where Speed Conversion is Used

  • Automotive industry
  • Aviation and aerospace
  • Maritime navigation
  • Astronomy and space exploration
  • Sports and athletics
  • Meteorology and wind speed
  • Computer and network speeds
  • Manufacturing processes