Fantin began his motorsport career like most racing in karting, where he was active until 2009. 2010 moved Fantin into formula racing and took for Hitech Racing Brazil participated in 9 of 24 races of the South American Formula 3 Championship. He won three races and it was a total of five times on the podium. In the overall classification, he finished the season in ninth place. He also completed for Hitech Racing nine guest appearances in the British Formula 3 Championship.
2011 received Fantin as a regular driver's cockpit at Hitech Racing in the British Formula 3 Championship. He chose a race for himself and finished the season on top of the eighth. 2012 moved Fantin within the British Formula 3 championship Carlin. With a win and seven podium finishes to Fantin improved to seventh place.
2013 Fantin entered for Arden Caterham in Formula Renault 3.5. With a seventh place as the best result, he finished the season off in 21st place. With 14 to 172 points, he defeated his teammate António Félix da Costa, who was third overall. 2014 moved Fantin within the Formula Renault 3.5 to International Draco Racing.
- 2010: South American Formula 3 ( 9th place)
- 2011: British Formula 3 (8th place )
- 2012: British Formula 3 ( 7th place)
- 2013: Formula Renault 3.5 (ranked 21)
- 2014: Formula Renault 3.5