Cheetahs are definitely the fastest land animals and many exaggerated claims about cheetah speeds have been made. One authority timed a cheetah with a stopwatch and recorded a speed of 114 km/h. A number of other claims of speeds in excess of 100 km/h have been made, although most of these claims are guesstimates.
One could probably accept that the average cheetah in its prime could reach 90 to 100 km/h, or slightly more.