Speed/Velocity Converter
Convert speeds between units such as metres per second, kilometres per hour, miles per hour, knots, and Mach number. Essential for physics, aviation, navigation, and various technical applications.
Convert Speed Units
Enter a speed value and select the units to convert between:
1 m/s = 3.6 km/h • 1 m/s = 2.237 mph • 1 m/s = 1.944 knots • Mach 1 = 340 m/s
Understanding Speed and Velocity
Speed and velocity are fundamental concepts in physics and everyday life. Speed is a scalar quantity (magnitude only) while velocity is a vector quantity (magnitude and direction). Different units are used in different contexts and applications.
Speed Unit Systems
⚡ SI Units (International System)
Meter per second (m/s): Base unit
Kilometer per second (km/s): High speeds
Used in physics and scientific calculations
Consistent with other SI units
🚗 Everyday Units
Kilometer per hour (km/h): Road speeds
Mile per hour (mph): US road speeds
Used for traffic, sports, and daily life
Intuitive for human-scale speeds
✈️ Aviation Units
Knots (kn): Nautical miles per hour
Mach number: Speed of sound ratio
Used in aviation and marine navigation
Standard for flight planning
Complete Speed Conversion Table
| Unit | Symbol | Meters per Second | Description |
|---|---|---|---|
| Meter per second | m/s | 1 | SI base unit of speed |
| Kilometer per hour | km/h | 0.2778 | Common road speed unit |
| Kilometer per second | km/s | 1000 | Used for astronomical speeds |
| Mile per hour | mph | 0.4470 | US customary speed unit |
| Knot | kn | 0.5144 | Nautical mile per hour |
| Foot per second | ft/s | 0.3048 | Imperial speed unit |
| Mach number | Mach | 340.29 | Speed of sound (sea level, 20°C) |
Common Speed Examples
| Object/Activity | Typical Speed | Description |
|---|---|---|
| Walking (comfortable) | 1.4 m/s | Average walking pace |
| Running (moderate) | 3.3 m/s | 8 mph running pace |
| Cycling (casual) | 6.7 m/s | 15 mph cycling speed |
| Car (city driving) | 50 km/h | Typical urban speed |
| Car (highway) | 100 km/h | Typical highway speed |
| Commercial jet | 250 m/s | Cruising speed of passenger aircraft |
| Sound (sea level) | 340 m/s | Speed of sound at 20°C |
| Space shuttle | 7,800 m/s | Orbital velocity |
| Light (vacuum) | 299,792,458 m/s | Speed of light |
Aviation and Marine Speed Systems
✈️ Aviation Speeds
Knots: Standard for aircraft
Mach: Supersonic flight
TAS: True airspeed
IAS: Indicated airspeed
CAS: Calibrated airspeed
🚢 Marine Speeds
Knots: Nautical navigation
Dead reckoning calculations
Current and tide effects
Port arrival times
Safety speed limits
🌊 Speed of Sound
Mach 1: 340 m/s (sea level, 20°C)
Mach 2: Supersonic (680 m/s)
Mach 5: Hypersonic (1,700 m/s)
Varies with temperature and altitude
Critical for aerospace design
Physics and Motion
⚛️ Speed vs Velocity
Speed: Magnitude only (scalar)
Velocity: Magnitude + direction (vector)
Average vs instantaneous
Uniform vs variable motion
Relative motion concepts
🚀 Space Physics
Escape velocity calculations
Orbital mechanics
Rocket propulsion
Interplanetary transfers
Light speed limitations
🏃 Sports Science
Running speed analysis
Cycling aerodynamics
Swimming velocity
Track and field timing
Performance optimization
Speed Limits and Regulations
🚗 Road Speed Limits
Residential: 30-50 km/h
Urban: 50-80 km/h
Rural: 80-100 km/h
Highway: 100-130 km/h
Vary by country and road type
✈️ Aviation Limits
VNO: Maximum structural speed
VNO: Normal operating speed
VA: Maneuvering speed
VSO: Stall speed
Safety speed margins
⚡ Speed of Light
c = 299,792,458 m/s (vacuum)
Approximately 300,000 km/s
Universal speed limit
Time dilation effects
Relativistic calculations
Speed in Different Environments
🌊 Water Physics
Wave propagation speed
Current velocity
Boat hull speed
Underwater vehicle speeds
Ocean current measurements
💨 Atmospheric Physics
Wind speed measurements
Weather front movement
Jet stream velocities
Tornado wind speeds
Atmospheric circulation
🔬 Particle Physics
Particle accelerator speeds
Relativistic velocities
Time dilation effects
Particle decay speeds
Quantum speed limits
🏃 Speed Tip: Remember that 1 knot equals 1 nautical mile per hour, which is why knots are used in aviation and marine navigation. Mach number represents speed relative to the speed of sound, which varies with temperature and altitude.