<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 recognize 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 according to ATP, 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 record for the fastest tennis serve