Speed Converter
Convert between speed units instantly. Transform miles per hour to kilometers per hour, knots to mph, and more. Essential for driving, aviation, marine navigation, and physics calculations.
How We Calculate This
All conversions use meters per second as the base unit. 1 mph = 0.44704 m/s, 1 km/h = 0.27778 m/s, 1 knot = 0.51444 m/s, 1 ft/s = 0.3048 m/s, Mach 1 = 343 m/s.
Frequently Asked Questions
How do I convert mph to km/h?
Multiply mph by 1.609 to get km/h. For example, 60 mph = 60 × 1.609 = 96.6 km/h. To convert km/h to mph, divide by 1.609.
What is a knot?
1 knot equals 1 nautical mile per hour, which is 1.852 km/h or 1.151 mph. Knots are used in maritime and aviation navigation.
What is Mach speed?
Mach 1 is the speed of sound, approximately 343 m/s or 767 mph at sea level. Mach 2 is twice the speed of sound, etc. The exact value varies with temperature and altitude.
How fast is the speed of light?
The speed of light is approximately 299,792,458 m/s or about 671 million mph. This is often denoted as "c" in physics.
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