Jan à ½elezný (; born 16 June 1966) is a Czech former track and field athlete who competed in the javelin throw. He is a World and Olympic champion and holds the world record with a throw of . Widely considered the greatest javelin thrower of the modern era, he also has the fourth, fifth and sixth best performances of all time. He broke the world record a total of four times.
à ½elezný was born in Mladá Boleslav, Czechoslovakia. He won the silver medal in the 1988 Olympics and the gold medal at the 1992, 1996 and 2000 Summer Olympic Games. He won World Championship titles in 1993, 1995 and 2001.
à ½elezný holds the world record of , set in 1996, and the World Championships record of , set in 2001. On 26 March 1997, in Stellenbosch, South Africa, he threw over the 90-metre barrier five times in a single meet. Until September 2020, he was also the only athlete to throw more than 95 metres with the new type of javelin, something he achieved three times.
During his career, à ½elezný had many great battles against the likes of Steve Backley, Sergey Makarov, Boris Henry, Seppo Räty, Raymond Hecht and Aki Parviainen.
à ½elezný planned to retire after the 2006 European Championships in Gothenburg, where he won the bronze medal with a throw of . He took leave of his career on 19 September 2006 on exhibition in Mladá Boleslav, the place where he started with athletics.
à ½elezný coaches VÃÂtÃÂzslav Veselý and is the former coach of Barbora à  potáková.
Four days after winning a gold medal at the 1996 Olympics, à ½elezný had a tryout as a baseball pitcher with the Atlanta Braves at Fulton County Stadium. Both à ½elezný and the Braves treated the tryout seriously and not as a "publicity stunt" or "sideshow", though à ½elezný had no baseball experience beyond throwing a ball at home with his young son.