Janosz began his motorsport career in karting in 2008 , in which he remained active until 2012. In 2013 he switched to formula racing and received a cockpit in the European F3 Open at Campos Racing . A sixth place was his best result and he finished the season as 13th team internally he was defeated by his teammate Valeria Carballo with 16 to 20 points. In 2014 Janosz moved to RP Motorsport within the series, which was now called Euroformula Open . He won two races and was on the podium nine times. In the championship he improved to second place. With 243 to 332 points he lost to his teammate Sandy Stuvik .
In 2015 Janosz received a cockpit at Trident Racing in the GP3 series . While his teammate Luca Ghiotto finished second in the championship with five wins, Janosz reached 14th place overall. In addition, he took part in an event of the European Formula 3 championship for EuroInternational . In 2016 Janosz completed his second GP3 season for Trident. With eighth place as the best result, he was 20th in the drivers' championship. In addition, he took part in a Formula V8 3.5 event for RP Motorsport .