Conversions
Speed converter
Convert a speed between miles per hour, kilometers per hour, meters per second, feet per second, and knots.
What this means
- 60 mph is 96.56064 km/h.
- 1 mph = 1.609344 km/h.
- Factors are exact definitions where one exists, so results are as precise as the display allows.
What if
About this calculator
What this calculator does
It converts between units by going through one base unit, the meter per second. Every unit has a fixed factor to the base.
How it is calculated
result = value * (factor of From) / (factor of To)
A mile is exactly 1,609.344 meters, a foot is 0.3048 meters, and a nautical mile is 1,852 meters. A knot is one nautical mile per hour.
How to read the result
The main result is rounded for display to at most eight decimal places. The other-units line shows the same value in several common units at once.
Sources and method
Exact conversion factors from NIST where they are defined. Unit tests check round trips and known values.
Questions
How do I convert mph to km/h?
Multiply by 1.609344. 60 mph is about 96.56 km/h.
What is a knot?
One nautical mile (1,852 meters) per hour. It is used at sea and in aviation.
How do I convert km/h to m/s?
Divide by 3.6.
Are these factors exact?
Yes. They come from the exact definitions of the mile, foot, and nautical mile.