Quick example
Convert 60 mph to km/h
Multiply 60 miles per hour by the exact mile-to-kilometer factor, 1.609344. The result is 96.56064 kilometers per hour, or approximately 26.8224 meters per second.
Quick reference
Common speed conversions
| Starting speed | Equivalent |
|---|---|
| 1 mph | 1.609344 km/h |
| 60 mph | 96.56064 km/h |
| 100 km/h | 62.1371 mph |
| 1 m/s | 3.6 km/h |
| 1 ft/s | 0.3048 m/s |
| 1 knot | 1.852 km/h |
| 1 knot | 1.15078 mph |
Unit definitions
Road, scientific, and nautical speeds
Miles per hour
Mph measures international miles traveled in one hour. It is commonly used for road speeds in the United States and United Kingdom.
Kilometers per hour
Km/h measures kilometers traveled in one hour and is the standard road-speed unit in most countries.
Meters per second
M/s is the SI unit of speed and is widely used in science, engineering, weather, and physics.
Knots
One knot is one nautical mile per hour. Knots are used in marine navigation, aviation, and weather reporting.
A fixed-distance converter
Why Mach is different
Mph, km/h, m/s, ft/s, and knots are fixed relationships between distance and time. Mach is a ratio to the local speed of sound, which varies with air temperature and atmospheric conditions. Leaving Mach out avoids presenting a changing physical value as an exact unit conversion. Displayed results use up to 12 significant digits.
Common questions
Speed conversion FAQ
How do I convert mph to km/h?
Multiply miles per hour by exactly 1.609344. For example, 60 mph equals 96.56064 km/h.
How fast is 100 km/h in mph?
100 kilometers per hour is approximately 62.1371 miles per hour.
How do I convert meters per second to kilometers per hour?
Multiply meters per second by 3.6. One meter per second equals exactly 3.6 kilometers per hour.
What is a knot?
A knot is one nautical mile per hour. It equals exactly 1.852 kilometers per hour.
Why is Mach not included?
Mach compares speed with the local speed of sound, which changes with temperature and atmospheric conditions, so it is not a fixed speed unit.