<P> This article lists the fastest recorded tennis serves in the men's and women's games . This list may not be historically complete . For instance, there are reports that Bill Tilden had a serve that was clocked at 163.3 mph but there is nothing to verify that . </P> <P> Although the Association of Tennis Professionals does not formally recognise service speed records made in Challenger events due to the variance in radar guns, the serve of 263.4 km / h (163.7 mph) recorded by Australian Sam Groth at an ATP Challenger event in Busan, South Korea in May 2012 was measured using approved equipment, and other data gathered appeared within a normal range . However, John Isner holds the official record for the fastest serve at 253 km / h (157.2 mph). </P> <P> Ivo Karlović with a 232 km / h (144 mph) second serve in the quarterfinals of the 2007 Legg Mason Tennis Classic in Washington, holds the record for the fastest second serve ever recorded . </P>

Who holds the world record for the fastest serve in tennis