🔄
Speed Converter - km/h, mph, knots, m/s
Free speed converter between km/h, mph, m/s, knots, feet per second, and Mach. Convert velocity units instantly for driving, aviation, and science.
Speed Converter
Convert between different speed/velocity units
Result
Enter your values to see results
and click the "Calculate" button
Speed Unit Conversion
Convert between common speed units including kilometers per hour (km/h), miles per hour (mph), meters per second (m/s), knots (nautical miles per hour), feet per second, and Mach numbers. Essential for driving, aviation, sailing, and physics.
How to Use
- Enter the speed value
- Select the source unit
- Select the target unit
- Click Convert
Common Conversions
1 km/h = 0.621 mph | 1 mph = 1.609 km/h
1 knot = 1.852 km/h = 1.151 mph | Mach 1 ≈ 1235 km/h (at sea level)
Frequently Asked Questions
How do I convert km/h to mph?
Multiply km/h by 0.621371. Example: 100 km/h = 62.14 mph. Or divide by 1.609.
What is a knot?
A knot is one nautical mile per hour (1.852 km/h or 1.151 mph). It's used in aviation and maritime navigation because nautical miles relate directly to latitude/longitude coordinates.
What is Mach number?
Mach is the ratio of speed to the speed of sound. Mach 1 = speed of sound (≈343 m/s or 1235 km/h at sea level). Mach 2 is twice the speed of sound.
Explore more calculators
100+ calculators for finance, health, math, and everyday life
All Calculators