Speed Converter
Velocity - walking pace to the speed of sound.
Enter a value above to convert between km/h and mph.
How to convert speed units
Speed is based on the meter per second. The handy rule is km/h = m/s × 3.6. For imperial speed, mph = km/h ÷ 1.609344 because one mile is 1.609344 km. A knot is one nautical mile per hour, which equals 1.852 km/h.
Worked example
To convert 60 mph to km/h: 60 × 1.609344 = 96.56 km/h. Going the other way, 100 km/h is 100 ÷ 1.609344 = 62.14 mph, and 10 m/s is 10 × 3.6 = 36 km/h.
How fast is 60 mph in km/h?
Sixty miles per hour equals 96.56 km/h. One meter per second equals 3.6 km/h, one mile per hour equals 1.609344 km/h (0.44704 m/s), and one knot equals 1.852 km/h. The speed of sound at sea level (Mach 1) is about 340.29 m/s, or roughly 1,225 km/h.
When you'll use a speed converter
Speed conversion is useful for driving abroad (mph and km/h), running and cycling pace, aviation and sailing (knots and mach), and physics. The table above lists your value in all 6 supported units at once.
Frequently asked questions
How many mph are in a knot?
One knot equals about 1.15078 mph. A knot is one nautical mile per hour, and a nautical mile is slightly longer than a statute mile, so a speed in knots is always a little higher when read in mph.
How do I convert m/s to ft/s?
Divide the meters-per-second value by 0.3048, since one foot equals 0.3048 meters. For example, 10 m/s divided by 0.3048 is about 32.81 ft/s.
What is the formula for converting ft/s to mph?
Multiply the feet-per-second value by 0.681818 to get mph, or equivalently divide by 1.46667. One mile per hour equals 1.46667 ft/s because a mile is 5280 feet covered in 3600 seconds.
Is a knot faster than a mile per hour?
Yes, a knot is faster. One knot is roughly 1.15 mph, so a vessel at 20 knots is moving at about 23 mph.
What is a mach number?
Mach is the ratio of an object speed to the local speed of sound. On this page Mach 1 (STP) is defined as 340.29 m/s, the speed of sound in air at standard temperature and pressure, so anything above Mach 1 is supersonic.
How many mph is Mach 1?
Mach 1 is about 761.21 mph at standard temperature and pressure. That comes from 340.29 m/s divided by 0.44704, the number of meters per second in one mph.
Popular speed conversions
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