Speed - a term that may mean two things; either the rate of changes through time, or a physical quantity that basically describes the rate at which an object covers distance.
d - distance
t - time
centimeter / second (cm/s), foot / second (ft/s), kilometer / hour (km/h), kilometer / minute (km/min), kilometer / second (km/s), knot (kn), mach (at std. atm.) (M), meter / minute (m/min), meter / second (m/s), mile / hour (mph), speed of light, speed of sound (at std. atm.), yard / second
About Speed Unit Conversion tool.
This Unit Conversion program uses custom rounding routines to avoid results such as 3.9999999999 instead of 4. It rounds the result to 13 significant digits instead of rounding to some number of decimal places, therefore producing superior results for very big or very small initial values and conversion factors. It accepts scientific notation and converts immediately.