🚀 Speed Unit Converter

Convert between mph, km/h, knots, mach, and m/s for automotive, aviation, and marine applications. Professional velocity converter.

Converter
Common Units
Formulas
Examples
Guide

Speed Converter

Common Speed Units

Miles per Hour
mph

Common in USA for vehicles. Highway speed limits typically 55-80 mph

Kilometers per Hour
km/h

Standard metric unit for vehicles. Highway speeds typically 90-130 km/h

Meters per Second
m/s

SI base unit for speed. Used in physics and scientific calculations

Knots
kn

Used in aviation and marine navigation. 1 knot = 1 nautical mile per hour

Feet per Second
ft/s

Common in engineering and ballistics. Used for projectile velocities

Mach Number
Mach

Speed relative to sound (≈343 m/s). Used in supersonic flight

🚗 Vehicle Speeds
• City driving: 25-35 mph (40-56 km/h)
• Highway: 55-80 mph (89-129 km/h)
• Race cars: 200+ mph (322+ km/h)
✈️ Aviation Speeds
• Commercial aircraft: 500-600 mph (Mach 0.8)
• Fighter jets: 1,200+ mph (Mach 1.8+)
• Sound barrier: Mach 1 (767 mph)
🌊 Marine Speeds
• Sailing boats: 5-10 knots
• Motor boats: 20-40 knots
• Speed boats: 50+ knots
🏃 Human Speeds
• Walking: 3-4 mph (5-6 km/h)
• Running: 8-12 mph (13-19 km/h)
• Sprinting: 15-28 mph (24-45 km/h)

Speed Conversion Formulas

MPH to KM/H
km/h = mph × 1.60934

Multiply miles per hour by 1.60934

KM/H to MPH
mph = km/h ÷ 1.60934

Divide kilometers per hour by 1.60934

M/S to KM/H
km/h = m/s × 3.6

Multiply meters per second by 3.6

KM/H to M/S
m/s = km/h ÷ 3.6

Divide kilometers per hour by 3.6

Knots to MPH
mph = knots × 1.15078

Multiply knots by 1.15078

Mach to MPH
mph = Mach × 767.269

Multiply Mach number by 767.269 (at sea level)

📐 Base Conversions
All speed conversions are based on meters per second (m/s) as the fundamental SI unit.
• 1 m/s = 3.6 km/h = 2.237 mph = 1.944 knots
🔊 Speed of Sound
Mach 1 varies with temperature and altitude:
• Sea level, 20°C: 343 m/s (767 mph)
• At 11 km altitude: 295 m/s (660 mph)

Quick Conversion Examples

60 mph → 96.6 km/h

Highway Speed

100 km/h → 62.1 mph

Metric Highway

10 m/s → 36 km/h

Scientific Unit

500 kn → 575 mph

Aircraft Speed

Mach 1 → 767 mph

Sound Barrier

25 mph → 11.2 m/s

City Driving

1000 ft/s → 682 mph

Ballistics

30 kn → 55.6 km/h

Boat Speed

How to Use This Speed Converter

Step 1: Enter Speed Value

Type the speed value you want to convert in the "From Speed" field.

Step 2: Select Source Unit

Choose the original speed unit from the dropdown (mph, km/h, m/s, knots, etc.).

Step 3: Choose Target Unit

Select the unit you want to convert to from the "To Unit" dropdown.

Step 4: View Result

The converted value will appear automatically in the "To Speed" field.

Step 5: Use Tools

Use the swap button (⇄) to reverse conversion, or copy/round the result as needed.

🎯 Conversion Tips
• Use decimal values for precise measurements
• Remember that Mach speed varies with atmospheric conditions
• Knots are based on nautical miles (1.852 km)
• For everyday use, mph and km/h are most common
🔧 Applications
• Automotive: mph ↔ km/h conversions
• Aviation: knots, Mach for flight planning
• Science: m/s for physics calculations
• Marine: knots for navigation
⚡ Quick Reference
• 1 mph ≈ 1.6 km/h
• 1 m/s ≈ 3.6 km/h ≈ 2.2 mph
• 1 knot ≈ 1.15 mph ≈ 1.85 km/h
• Mach 1 ≈ 767 mph ≈ 1,235 km/h