Speed Converter

Convert between different units of speed and velocity.

1 Kilometers per Hour = 0.6213716893 Miles per Hour

Quick Conversions

m/s: 0.277778
mph: 0.621372
ft/s: 0.911345
kn: 0.539958
Ma: 0.00081

About Speed Conversion

Speed (or velocity) measures how fast something is moving. It is expressed as distance traveled per unit of time.

Common Conversions

  • 1 km/h = 0.621371 mph
  • 1 mph = 1.60934 km/h
  • 1 m/s = 3.6 km/h = 2.237 mph
  • 1 knot = 1.852 km/h = 1.151 mph
  • Mach 1 ≈ 343 m/s = 1,235 km/h (at sea level)

When to Use Different Units

  • km/h: Road speeds (most countries)
  • mph: Road speeds (US, UK)
  • m/s: Scientific measurements, physics
  • Knots: Maritime and aviation
  • Mach: High-speed aircraft, supersonic speeds

Quick Reference Speeds

  • Walking: ~5 km/h (3 mph)
  • Running: ~10-15 km/h (6-9 mph)
  • City driving: ~50 km/h (30 mph)
  • Highway: ~100-130 km/h (60-80 mph)
  • Commercial aircraft: ~900 km/h (560 mph)
  • Speed of sound: ~1,235 km/h (767 mph)