Kszczot reached the international level after competing in local and then national events. He won the bronze medal at the
2007 European Junior Championships, finished fourth at the
2008 World Junior Championships and won the
2009 European U23 Championships. He finished fourth at the
2009 European Indoor Championships and competed at the
2009 World Championships without reaching the final. Kszczot won the bronze medal at the
2010 World Indoor Championships and the
2010 European Championships, as well as the gold at the
2011 European Indoor Championships. He reached the final at the
2011 World Championships, finishing sixth. His outdoor personal best is 1:43.30 minutes, achieved on 10 September 2011 in
Rieti. in
Gothenburg. Kszczot broke
Paweł Czapiewski's 10-year-old
Polish indoor record at the 2012
Meeting Pas de Calais. His time of 1:44.57 made him the third fastest indoor runner ever after
Wilson Kipketer and
Yuriy Borzakovskiy. Vazel, Pierre-Jean (2012-02-15). With this result, Kszczot went to the
2012 World Indoor Championships as a medal favourite. However, he finished a disappointing fourth. In his Olympic debut in
London he placed third in his semifinal round, failing to qualify for the final. He started well in the 2013 season by successfully defending his title at the
European Indoor Championships, the first man to do so in 42 years. On August 15, 2014 he won the
men’s 800 m final at the
2014 European Athletics Championships with a time of 1:44:15 after a blistering last 100 m sprint. In 2017, he won the bronze medal in the
men's 4 × 800 metres relay at the
2017 IAAF World Relays held in Nassau, Bahamas. He won the silver medal in the 800 metres at the
2017 World Championships held in London. On March 3, 2018 Kszczot claimed his first title of
World Indoor Champion in the 800 meters. He controlled the final run, the pace of which was quite slow and won with a large advantage over American
Drew Windle and Spanish
Saúl Ordóñez. He dedicated his gold medal to his 5-month-old son Ignacy. In August, Kszczot added the European outdoor title at the
event. ==Achievements==